Turns over but wont start!!!


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dmorlow
12-13-2004, 07:56 PM
I just want to have everybody’s consensus. I drove my car home last night and the car ran great. I went out to my car this morning and it won't start. It turns over. The battery is fully charged and it is turning over good. I don't smell gas so I am sure it is not flooding or that I don't have spark or anything like that. There is no smell of gas what so ever. So I am pretty sure it has to be something to do with the fuel system. I took off the fuel line that goes from the tank to the engine, turned over the engine, and no gas came out at all. But is there anything other than the fuel pump that could cause this? Maybe a sensor that went bad that is not telling the car to send gas? I just want to make sure there is nothing else that could make the car not get gas other than the fuel pump. The pump is $300 and I don't want to throw that away!!!

Isnibs
12-13-2004, 09:44 PM
Have you checked the Fuel Pump Fuse??

Rezarecter
12-14-2004, 02:01 AM
The fuel pump fuse in my car blew like 3 days after I bought it. My dad flipped out on my saying i never should have bought the car, because he thought it was a dead fuel pump. It felt good to see it was just the fuse, and that I bought the car and it still works 6 months later.

That is all.

dmorlow
12-15-2004, 12:00 PM
I will be really mad (or happy... I don't know) if that is it. I never thought about checking that. I already ordered a new fuel pump. Had to order it through the mail seeing I can't find anyone that sells an AC Delco fuel pump locally. Hopefully they take it back if this is it.

dmorlow
12-15-2004, 06:49 PM
Ok, now I am looking at a flow chart for troubleshooting a car that doesn't start that turns over in the manual for my car. One thing it says is to remove the fuel relay and replace it with a "fused b+." I take it that it has to have the same connector as the relay. After that, it has you do some tests with this "fused b+" in place of the fuel relay. But does anyone know what a "fused b+" is?

Retro-D
12-15-2004, 09:23 PM
Ok, now I am looking at a flow chart for troubleshooting a car that doesn't start that turns over in the manual for my car. One thing it says is to remove the fuel relay and replace it with a "fused b+." I take it that it has to have the same connector as the relay. After that, it has you do some tests with this "fused b+" in place of the fuel relay. But does anyone know what a "fused b+" is?
"Fused B+" would be a piece of wire with an inline 15 amp fuse connected to the battery positive terminal. If you are looking at the instructions on page 6E3-A-83 they are saying to connect fused B+ lead to terminal 87. If you look at the schematic what this does is bypass the relay and feeds power direct to the fuel pump. They advise to remove the gas cap and listen to hear if the pump is running when energized....okay?

RD

dmorlow
12-16-2004, 01:39 AM
How in the world do they expect for you to know that a "fused b+" equals a 15 amp fuse? I don't see it anywhere in the book saying that the fused b+ equals 15 amps. Where did you figure it out?

Retro-D
12-16-2004, 06:41 AM
How in the world do they expect for you to know that a "fused b+" equals a 15 amp fuse? I don't see it anywhere in the book saying that the fused b+ equals 15 amps. Where did you figure it out?
Consider who created the books. The factory books were written for people who had some degree of factory or formal training. The geek term "B+" was commonly used in early radio and electronics and in this case denotes 'battery plus'. Anyway, I have decoded the passage for you so you can proceed with your testing.
PS: The 15 amp fuse came from reading the schematic diagram, same value the factory uses...
Good Luck,

RD

dmorlow
12-17-2004, 04:29 PM
Well, an update. The fuse isn't blown. And, just to be on the safe side, I replaced the fuel relay. Didn't help. So I'm pretty sure it's the fuel pump. I ordered it a few days ago and should be here sometime next week. (I still can't believe that one one locally stocks these fuel pumps.)

Retro-D
12-17-2004, 08:08 PM
Well, an update. The fuse isn't blown. And, just to be on the safe side, I replaced the fuel relay. Didn't help. So I'm pretty sure it's the fuel pump. I ordered it a few days ago and should be here sometime next week. (I still can't believe that one one locally stocks these fuel pumps.)
If you follow the troubleshooting procedure and supply "fused B+" to terminal 87 and then listen for the pump you will know for sure if it runs or not. The relay you changed is controlled by the PCM and may not be activating, I would exhaust all possibilities before changing out the pump. Once you know the pump is running put a fuel pressure gage on the rail (under the engine cover) and check the pressure.

RD

dmorlow
12-17-2004, 09:47 PM
According to the flow chart in the GM manual, if the relay is good (which it is for sure because it is brand new now), the only other thing to test is right at the fuel pump. And that test is to check for any kind of opens in the circuit, which I can't do until the gas tank is off. But I highly doubt that is the issue. But there is no spot inside the engine to connect a pressure guage on this engine. I took off the engine cover. There may have been one at one time, but I just had that recall done where they put all new gas lines from the fuel rail all the way back to the gas tank. There is no connector there anymore to check the fuel pressure. But I did take the gas line off and turn over the car and no gas came out, so I feel pretty confident that the fuel system is not working. But how would I test the PCM anyway?

dmorlow
12-17-2004, 11:33 PM
I guess the more I think about it, if the relay that I replaced was good, then by replacing it, I ruled out nothing. Then it could be a computer or something else in the car somewhere. So does anyone know how I could go about doing more tests? The part I don't understand about applying a fused b+ to terminal 87 is there has to be two contacts that I have to put the fuse to. So what two terminals do I apply it to? 87 and what? Is the other one ground? Or is it something else?

Retro-D
12-18-2004, 10:29 AM
I guess the more I think about it, if the relay that I replaced was good, then by replacing it, I ruled out nothing. Then it could be a computer or something else in the car somewhere. So does anyone know how I could go about doing more tests? The part I don't understand about applying a fused b+ to terminal 87 is there has to be two contacts that I have to put the fuse to. So what two terminals do I apply it to? 87 and what? Is the other one ground? Or is it something else?

Yes, I see the light bulb over your head is coming on, changing the relay doesn't mean much at this point. The fused B+ lead is a simple piece of wire with a 15 amp fuse connected in series with the wire. Connect one end to the battery in your car (positive terminal). The other end of the lead goes to terminal 87. Be sure to unplug the relay during this test. Once this is done you are bypassing the PCM and relay, you will be feeding 12 volts directly to the pump via your 'b+' test lead. Remove the gas cap and listen to hear if the pump is running.

PS: Picture link to what a fuse b+ lead will look like:
http://www.holtallen.com/im/Q897.jpg

RD

dmorlow
12-18-2004, 02:27 PM
Ok, I just did the test. I ran one side of the fuse straight to the positive terminal of the battery and the other side straight to terminal 87, opened up the gas cap and listened and I heard nothing. So the next step in the flow chart is to disconnect the connector at the fuel pump and run another test to see if there's a short in the circuit between the relay and the pump. But I am not going to do that until I have the fuel pump in hand. So that won't be until next weekend.

Retro-D
12-18-2004, 07:18 PM
Ok, I just did the test. I ran one side of the fuse straight to the positive terminal of the battery and the other side straight to terminal 87, opened up the gas cap and listened and I heard nothing. So the next step in the flow chart is to disconnect the connector at the fuel pump and run another test to see if there's a short in the circuit between the relay and the pump. But I am not going to do that until I have the fuel pump in hand. So that won't be until next weekend.

If the new pump won't run when you plug it in then it's the wiring from the relay to the pump, or a bad ground connection from the pump to the chassis.

Good Luck,

RD

dmorlow
12-27-2004, 01:28 AM
Ok, an update. I ordered my fuel pump. I got it in the mail a few days ago. I started on it yesterday. I was really suprised on how to replace the fuel pump though. I started to take off the exhaust because it goes right under the fuel tank. Then I noticed all of the other stuff that was in the way of taking out the tank. It was insaine. So I finally got out the manual and noticed that I can access the fuel pump right through an access hole in the trunk. I've never seen that feature in a car before. That is the coolest feature. Do other cars have that little access hole these days to change out a fuel pump these days? But the ring that goes around the fuel pump that holds the pump to the tank came off really hard. I had to basically break off the ring to get it off. Now the ring is destroyed and the new pump did not come with one. So now I need to figure out where to get one of those. Anyone else have that problem?

dmorlow
12-28-2004, 06:32 PM
Question for everyone now. I bought one of those rings from the dealer (only $5 or so). I put the pump in and the car started right up. The ring that goes around the pump that slides into the grooves that holds the gas tank in, I'm having a little problem with though. When putting it on, I can get the ring to turn far enough right before it gets to the "hump." There's like a ridge in the ring. If I can get it over that ridge, then it will press down on the fuel pump harder. But I banged on it for a while and couldn't get it past the hump. My car does run, but my car has a scent of gas in it now. When I first get in the car, it seems pretty strong. But as I drive, it goes away. I'm not sure if it goes away because I'm getting slightly high, or if it really goes away (mostly). But if I could get it past that "hump" in the ring, it would press down on the pump harder and put a tighter seal on the pump and then maybe get rid of the gas scent. Does anyone know if I am supposed to be able to get it past the hump in the ring? Is there a special tool to turn that ring? (I don't know what the old one was like because when I took it off, it was so rusted and dirty, I had to break it off in small pieces.) Or maybe am I getting the gas scent in the car because I haven't put the cover over the pump yet in the trunk and the fabric lining back in the trunk?

Isnibs
12-28-2004, 07:05 PM
Did you install the 'O' ring first?
You need a wrench Part No.J39765 to tighten it (1996 info yours may be different)
I wouldn't drive the car until you do.

dmorlow
12-28-2004, 08:17 PM
No, I didn't install the oring first. You need to put the fuel pump in first. Then the oring goes around the top of it. If you were putting the oring in first, then maybe you were doing it from the bottom up. Did you take the tank out? I didn't take out the tank. I did it through the trunk. So you have to put the pump in first. Then use the ring to hold it in. But thanks for the wrench part number!!!

Isnibs
12-28-2004, 08:39 PM
The instructions must be different for my 1996 because they definitely state to put the 'O' ring in first (working from the trunk)

dmorlow
12-28-2004, 08:57 PM
By the way, where did you find this part number for the wrench? Where can I buy one? I've called all over the city since I read this and searched all over the web. No one's heard of the tool and I can't find it on the web anywhere.

Isnibs
12-28-2004, 10:14 PM
First the info I gave you is for a 1996 Aurora and is probably different for your 1995 so it is pointless looking for any wrench until you know it is the correct one.
Maybe ask the forum for help from a member with a 1995 manual or get one.
BTW. I get my info from a 1996 Aurora Repair/Service/Manual.

Retro-D
12-29-2004, 06:28 AM
The 1995 FSM lists the same wrench part number. I suppose you either have to make one or buy the 'specialty' tool (link below).
http://www.etoolcart.com/browseproducts/Fuel-tank-sending-unit-wrench-J-39765.HTML

RD

dmorlow
12-31-2004, 05:41 PM
Ok, I am pretty sure it is fixed now. I made a tool to tighten it. I took the metal ring and punched some spots in the corners of the ring on a piece of metal. Then I drilled holes in the corners. Then I put some screws threw the holes and tightened them down with bolts. Then I welded a bolt on top of the metal in the center of the screws. Then I put the pump back in, put the ring over it, and then I was able to turn it with the tool I made. It turned right in like a charm. It turned all the way past the humps. I think everything is fine now. Thanks for everyone's help!!!

Isnibs
12-31-2004, 08:50 PM
Great.
it's good to hear that your Aurora is up and running again. Well done with the tool, saved yourself a lot of money and trouble.

dmorlow
01-03-2005, 07:34 PM
Ok, this car is starting to drive me nuts now. Everything worked great until this morning. Went out to start my car and DEAD again!! Turn on the key and the fuel pump isn't even turning on again. I just ran the same tests I ran before I changed out the pump. I took the fused 12 volt wire and ran it straight to pin 87 on the fuel pump relay. I opened up the gas cap and listened and I heard nothing. According to the GM manual, this is supposed to bypass the relay and just turn on the fuel pump. It's running 12 volts straight to the fuel pump this way. Well, that lead me right back to the fuel pump again. I would like to think this pump isn't dead already. It's a brand new AC Delco fuel pump. So I ripped my trunk apart again and checked the wiring to the pump. At that point, I hadn't even touched the wiring. Just looked at it. For some reason, I just felt like trying to start my car again. To my amazement, my car started right up. I got in my trunk and wiggled the wires to see if maybe a bad connection and the car did not stall. Now another puzzle to the problem is, last night on the way home, my check engine light came on. (I have another post yesterday about this issue. I didn't think they had anything to do with the old problem yesterday seeing the car still ran great.) I happen to own my own Snap-on 2500 scanner. These are the codes...

36 EGR Pintle Position out of range
52 Defective ECM (ECU RAM Chip Error)
70 Intermittent throttle Position
109 Internal ECM Problem (KAM checksum)

When my car died the first time, I never got a check engine light so I have no idea if this error light is completely unrelated or what.
Now it did seem that when my car started a few minutes ago, it was running maybe slightly rough. Another mystry to the puzzle though is to do the tests that I was doing earlier, you have to pull the fuel pump relay to put the fused b+ wire to pin 87. When I went to start my car up, I forgot to put the fuel relay back in. But, for some reason, the car started right up and ran for a few minutes (did not stall, I turned it back off) without the fuel relay in. Does it make sense the car would run without the relay in? I am sure it is the correct relay. The cover shows the relay and it has a corresponding letter. The letter of the diagram matches the letter under the physical relay.

P.S. I am about ready to drive this car off a cliff soon!!! I hate this car!!!

chris_fit
01-03-2005, 07:40 PM
try unhooking the battery, letting it sit for a few min, then connecting it again. That should clear the computera nd see if the codes come back.

dmorlow
01-03-2005, 07:43 PM
I already erased the codes with my scantool. But do you think that unhooking the battery for a while would help anyway?

Retro-D
01-03-2005, 08:34 PM
Ack!!! I believe I read that the Aurora will still run if the fuel relay fails because the oil sender acts as an emergency back-up to keep voltage on the pump. Remember, the pump still needs it's ground return to complete the circuit. I now wonder if your old pump is still good?

RD

dmorlow
01-03-2005, 09:39 PM
I'm pretty sure I checked the right fuel line. My dad made some sense of the lines. There's one line that has a small line connected to it. He says the small line is a return line in case the fuel pump sends too much fuel. So we disconnected the big line that is next to the small line and turned over the engine and nothing came out. I already replaced the fuel pump so it wouldn't be wiring inside the tank. It is possible it's wiring going to the pump. But with my tests earlier, I'm confused about what it could be now. (And I know about the access panel inside the trunk. I am so thankful about that. Sure beats pulling the tank!!!)

GuMan
01-03-2005, 09:47 PM
Ack!!! I believe I read that the Aurora will still run if the fuel relay fails because the oil sender acts as an emergency back-up to keep voltage on the pump. Remember, the pump still needs it's ground return to complete the circuit. I now wonder if your old pump is still good?

RD
Yes.. the oil pressure switch actually works, when the oil
is cold. Don't rely on this on a hot day with a hot engine.
It needs enough pressure to make, and it doesn't always
get it when turning over hot.

It sounds like you have a gremlin. I had similar issues and
decided to replace the PCM. I found that two +5V reference
regulators had started to go. Unfortunately, they were made
by the company I used to work for. I know the guy who
let these go out the door. I gave him a hard time about it.
These were used as references for things like the EGR and
TPS. They were moving around and causing the PCM to think
the sensor was moving.

The PCM on my '95 was not too expensive from GMPartsdirect.
It is real easy to replace, just remember that they don't send
you a new PROM. If you have a 1996 or newer, you have a
flash programmable PROM, and could have a dealer reflash
your PCM for you. That will check the PROM and make sure
it is not faulty.

GuMan
01-03-2005, 09:54 PM
The order of the fuel lines can be determined as
follows. If you remove the engine cover and
find the fuel pressure regulator on the back
of the fuel rail, follow the line down from there.
This is the fuel return line. The fuel pressure
regulator works by blocking the fuel going back
to the tank until it's pressure (spring and vacuum)
is met, then the diaphram lets the fuel go back
up this line. The other line that goes to the front
of the fuel rail is the fuel feed line from the pump.
The connector near the first fuel injector should
have a Schrader (bicycle) type of valve that
you can put a pressure gauge on, or carefully
push the center pin on to see that there is
fuel pressure there, when the pump is on.

The third line is from the back behind the throttle
and is the fuel vapor pipe.

dmorlow
01-04-2005, 04:59 AM
So, what would be the next logical thing to try to figure out what is wrong with my car?

dmorlow
01-06-2005, 02:34 AM
Ok, I don't know if something really wacko is happening to my computer or what, but I've received 2 e-mail notifications saying someone updated this forum. Yet when I visit the thread, the last post is my post asking what to do next. I don't know if the forum is going crazy and sending me updates saying someone added something, or if people really are and I can't see the comments!!!

willers227
01-06-2005, 08:13 AM
im having this same problem

dmorlow
01-08-2005, 02:59 PM
Ok, I'm not making too much headway with this car anymore. But I also have this other problem with the car and I don't know if they have anything to do with my original problem. For quite a while, when I shutoff my car, I get this clicking sound from my engine for a few seconds. I found an article on the issue...

Throttle Body - Clicking Noise Under Dash or Hood

File In Section: 6 - Engine

Bulletin No.: 47-60-07

Date: December, 1994
Subject:
Clicking Noise Under Dash or Hood (Clean Throttle Body Bore and Blade)

Models:
1995 Cadillac Concours, Eldorado, Seville
with 4.6L Engine (VINs Y, 9 - RPOs L37, LD8)
1995 Oldsmobile Aurora with 4.0L Engine (VIN C - L47)

Condition

During a-KEY ON" or "KEY OFF," the ISC motor may ratchet. The condition may be identified as a clicking noise under dash or hood. The duration of this ratcheting may be up to 20 seconds. The ratcheting condition may occur more frequently when starting the engine cold or at higher altitudes.

Cause

The ISC motor ratcheting is caused when the motor is commanded to extend beyond its mechanical limit. When the TP sensor learn is correct (at minimum air, the throttle lever rests on the minimum air screw) and the ISC maximum extend position is properly adjusted, the motor will not be commanded to move beyond the mechanical limit.

Correction

The throttle body bore and blade should be cleaned and relearned using the following procedure:
Important : If it is suspected that the ISC maximum extend position had been adjusted without cleaning the bore, it should be checked and readjusted if required. Cleaning the throttle bore should be performed before performing the idle speed control system checking procedure.

Throttle Body Cleaning Procedure

Remove or Disconnect

Air intake duct from throttle body.

Inspect
Throttle body bore and throttle valve plate for
deposits. It is necessary to open the throttle valve to
inspect all surfaces.

Clean
Throttle body bore and throttle valve plate using a
clean shop towel with GM Top Engine Cleaner,
P/N 1052626 or AC-Delco Carburetor Tune-Up
Conditioner, P/N X66-P, or equivalent product.

Notice : Do not use any solvent that contains Methyl
Ethyl Ketone (MEK). This solvent may damage fuel
system components.

FOR G CAR

Install or Connect
1. Air intake duct at throttle body.

2. Run Tech 1 TP sensor and idle learn procedure.

FOR E, K, AND/OR K SPECIAL

Install or Connect
1. Air intake duct at throttle body.

2. Enter diagnostics; select PCM override PS13.

3. Press the "COOLER" button.

4. Key "OFF" for 30 seconds (do not exit diagnostics).

5. Perform TP sensor/idle learn procedure.

Warranty Information



For vehicles repaired under warranty, use.


I happen to own a snapon 2500 scanner. I hooked it up to my car and ran the TP sensor test. According to my scanner, the TP sensor is using 1 to 1.5 volts. It's supposed to be using 0.5 +/- 0.05 volts. I am not sure how to adjust the TP sensor. Any ideas? Or do I just need to buy a new one? Autozone has them for $20. Does everyone think that there's a chance this is what is wrong with my car? Or am I on the wrong track? (It's broken anyway so I'm going to fix it. But I know most likely it won't fix my original issue.)

dmorlow
01-08-2005, 09:11 PM
Ok, today I was working on my car again. I decided to work on that clicking in the engine. I bought a replacement TP sensor. It makes me mad. I bought it from Autozone and they gave me the wrong one. But I was trying to put the wrong one on because I didn't notice it was slightly different at the time. Then I started up the car and my check engine light came on. I scanned my car again and I got two codes this time.

22 throttle position sensor too low (because they gave me the wrong sensor. i put the old one back on for now.)

20 fuel pump open or shorted to ground.
I can almost guarantee the last one is why my car is not running right. At least I hope it is. I just have no idea on how to figure out where it is messed up in the wiring. I think I am going to take it to a shop for this now.

GuMan
01-09-2005, 06:37 PM
I very often get the TPS relearn upon turning off the car.

I have a 1995 and I have gone through a throttle body and
intake cleaning twice, myself, and forced the PCM to relearn
the TPS position.

What I am getting at is that a lot of the OBD1 PCMs do this
no matter what. It does not set a code or cause any problems.
I would be surprised if your TPS is bad and you haven't gotten
any codes for it before. They typcially start to get flaky before
going altogether. Also, I don't think you can adjust the angle
you install them on, like you could on older vehicles. Which is
good, since you just have to line it up the way they have
it set up.

Your fuel pump code sounds more likely, as you indicated
earlier you still had problems with getting fuel pressure
at the manifold. There are not too many places for the
fuel pump wiring to have problems, if you don't consider
the bulk of the wire length and just concentrate on the
connectors. One item to look into is the oil pressure
switch on the engine. As mentioned before, this switch
is setup in parallel to your fuel pump relay, so if the relay
goes bad, the oil pressure switch will get you home. If
the wiring there is quesitonable, it could cause problems.
Typically, you would also see a low oil pressure light on
the dash. You may want to find this pressure switch and
disconnect the wire from it until you get this started. You
can use it to meter the voltage from the pump side of
the relay, too.

The main places are the relay socket itself and then the
plug on the fuel pump. If you are sure these are in
good shape, I can't think of anything else that could
cause that code. It is caused by the sense line on the
fuel pump side of the relay not being up near +12V when
it is supposed to.

Something like this could have been your problem all along.

dmorlow
01-10-2005, 07:46 PM
It made me so mad today. I went to the dealer to talk to them about the problem. I asked for them to look up to see if there's a bulletin on the issue I'm having. They found a bulletin. It was titled something like "Intermittent stalls and intermitent starts." They were reading off the description and it sounded exactly what was wrong with my car. I asked them if I could get a copy of the article or read it, and they said no. It made me so mad. The answer to my problems so close and I can't see it. But I ordered a new wiring harness to hook into the fuel pump. Hopefully that fixes it. But has anyone seen this bulletin?

dmorlow
01-28-2005, 10:27 PM
Ok, now I'm clueless on what to do. I finally brought it to a shop. The shop around here has a pretty good reputation. Well, they kept the car for 3 days. It had a day they couldn't get it to start. They gave the car back to me today. They basically shrugged their shoulders and said "I don't know." At least they didn't charge me anything for 3 days of diagnosis but they didn't have a clue either. I am completely out of ideas now.

Retro-D
01-28-2005, 11:37 PM
Ok, now I'm clueless on what to do. I finally brought it to a shop. The shop around here has a pretty good reputation. Well, they kept the car for 3 days. It had a day they couldn't get it to start. They gave the car back to me today. They basically shrugged their shoulders and said "I don't know." At least they didn't charge me anything for 3 days of diagnosis but they didn't have a clue either. I am completely out of ideas now.
Did you say you changed the wiring loom to the new fuel pump and the new pump does not work sometimes??

RD

dmorlow
01-29-2005, 05:20 AM
NO, I haven't tried changing that yet. Actually I have a new wiring harness that I could try putting on, but I am starting to feel like that isn't the problem anymore. (Seeing I am not convinced that's causing the problem seeing the old one looks perfect, I would rather not cut the original one off and have a new one spliced on. Spliced connections are never as good as the original connection.) I am starting to steer away from the fuel pump and looking elsewhere now. I am kind of suspecting the ECM maybe. But now that is going to be a $200 try.

Retro-D
01-29-2005, 08:07 AM
NO, I haven't tried changing that yet. Actually I have a new wiring harness that I could try putting on, but I am starting to feel like that isn't the problem anymore. (Seeing I am not convinced that's causing the problem seeing the old one looks perfect, I would rather not cut the original one off and have a new one spliced on. Spliced connections are never as good as the original connection.) I am starting to steer away from the fuel pump and looking elsewhere now. I am kind of suspecting the ECM maybe. But now that is going to be a $200 try.

Before I would shell out anymore $$$ I would leave a multimeter connected to the fuel pump voltage feed wire at all times. You need to confirm the pump is losing voltage and work it forward or back. I understand how frustrating it is with electrical problems but the 'shotgun' approach can get very costly.

RD

dmorlow
01-29-2005, 09:49 AM
Well, these are the codes I got out of my car after I changed my fuel pump. Two codes say that I have a defective ECM. I think I'm also going to replace the throttle positioning sensor also. That's probably not causing this problem. I get a clicking sound under my hood from my throttle body trying to go beyond its mechanical limits and that would fix that problem.
The EGR Pintle Position out of range... I am not sure what to do about that one.

36 EGR Pintle Position out of range
52 Defective ECM (ECU RAM Chip Error)
70 Intermittent throttle Position
109 Internal ECM Problem (KAM checksum)

dmorlow
01-29-2005, 09:50 AM
To be honest, I am not sure why I didn't replace the ECM earlier. I was just so focused on the fuel pump and convinced that the fuel pump or something related to the fuel pump was the issue, I completely ignored the ECM error.

Retro-D
01-29-2005, 10:03 AM
To be honest, I am not sure why I didn't replace the ECM earlier. I was just so focused on the fuel pump and convinced that the fuel pump or something related to the fuel pump was the issue, I completely ignored the ECM error.

Maybe some of the other codes will clear when the ECM is changed. You might try cleaning the EGR later if the code remains, otherwise more $$. Good luck & keep us posted.

RD

dmorlow
01-30-2005, 07:05 PM
Well, I changed out my ECM and it made things worse. Now my check engine light is on constantly. I can't get it to go off. (I have a Snapon 2500 scanner. I've gone in and cleared the codes and code 80 will not go away.) The car is shifting wierd now. It waits abnormally long to shift to second gear. Then it immediatly shifts to 3rd gear. Then it doesn't ever go into overdrive. I think the ECM I got was faulty right from the get go. My car drove worse with the new ECM compared to the old one. So I've put in the old one. I am now just going to take my car to another shop and tell them to do whatever it takes to make my car drive nice again. I am so sick of this car!!!

dmorlow
02-03-2005, 10:52 PM
Ok, I took my car to another tech. They replaced my throttle positioning sensor. I don't understand why my car is running better now. Actually it's running pretty much perfect. When I replaced it, it ran just as bad. I just can't imagine the chances that the first one was bad. Then I replaced it with a brand new one, and that one quincidently was bad and was causing the same exact issue. Then he replaces it and now the car runs perfect. I don't know if the original problem is just dorment right now and it is going to come back in a few days or weeks. Does it make sense that a TP sensor could cause the car to not be able to start all together and cause my car not to have any fuel pressure (the symptom I was having from the start)? When I was replacing it, I was replacing it to fix a completely seperate issue with my car and didn't imagine in a million years it was going to fix the issue with my car not starting.

Retro-D
02-03-2005, 11:07 PM
Ok, I took my car to another tech. They replaced my throttle positioning sensor. I don't understand why my car is running better now. Actually it's running pretty much perfect. When I replaced it, it ran just as bad. I just can't imagine the chances that the first one was bad. Then I replaced it with a brand new one, and that one quincidently was bad and was causing the same exact issue. Then he replaces it and now the car runs perfect. I don't know if the original problem is just dorment right now and it is going to come back in a few days or weeks. Does it make sense that a TP sensor could cause the car to not be able to start all together and cause my car not to have any fuel pressure (the symptom I was having from the start)? When I was replacing it, I was replacing it to fix a completely seperate issue with my car and didn't imagine in a million years it was going to fix the issue with my car not starting.

I hope all your troubles with the car are solved. I guess time will tell if the TPS was really the problem. Did you get another replacement ECM or are you back to the original?

RD

dmorlow
02-04-2005, 12:21 AM
I'm actually back to using the original ecm.

dmorlow
02-05-2005, 06:36 AM
Ok, new update. The TP sensor didn't fix it. I went out to start my car yesterday and it didn't start. Any more ideas?

Retro-D
02-05-2005, 08:37 AM
Ok, new update. The TP sensor didn't fix it. I went out to start my car yesterday and it didn't start. Any more ideas?

Scan for codes. Swap the ECM again to rule out the old one being intermittent.

RD

GuMan
02-05-2005, 01:30 PM
Most replacement ECM's don't come with an EEPROM.
You need to swap the EEPROM's out. Are you
swapping the EEPROM from your original ECM
to the new ECM?

If so, there could be a reliability issue with the
EEPROM. When this type of EEPROM fails, it
usually appears as data degeneration, or not
flashing correctly. Since your ECM is writing into
the EEPROM constantly, that is where your program
defaults and measured ranges are stored, this
could cause big problems. The only way the
EEPROM is checked by the ECM for errors is by
checksum (there is an error code for this) and
this method does not pick up many problems with
the EEPROM.

When you purchase a replacement ECM, you need
to be very specific to which part number you get.
There are typically 2 to 3 revisions of ECM module
per model year, never mind the EEPROM variations.

Unless you've purchased the right ECM and EEPROM
I suspect your EEPROM could be the culprit here.

dmorlow
02-05-2005, 02:02 PM
I did swap out the EEPROM when I did the ECM. But you are saying that it is possible that the EEPROM is bad?
Again, here are the codes I pulled from my car...

36 EGR Pintle Position out of range
52 Defective ECM (ECU RAM Chip Error)
70 Intermittent throttle Position
109 Internal ECM Problem (KAM checksum)

GuMan
02-06-2005, 04:01 PM
I did swap out the EEPROM when I did the ECM. But you are saying that it is possible that the EEPROM is bad?
Again, here are the codes I pulled from my car...

36 EGR Pintle Position out of range
52 Defective ECM (ECU RAM Chip Error)
70 Intermittent throttle Position
109 Internal ECM Problem (KAM checksum)

I couldn't tell you if your EEPROM is no good or not. Your
dealership should be able to. There are many more areas
in the ECM memory map that they have access to that
you do not. Also, they can "try" a different EEPROM to see
if it makes a difference before you buy it.

Did you protect yourself from static discharge
when changing the ECM and EEPROM? A spark with as little
as 200V between you and it is enough to cause damage to
many electronics of this type.

Two of your codes seem to make me think there is a voltage
regulator problem, and the other two make me think there is
a memory controller issue in the ECM.

Codes 36 and 70 can both be caused by a flaky 5V regulator
in your ECM. One of my co-horts was the product engineer
for many of these 5V regulators. This causes the signal coming
back to the ECM to move around, even though the sensor is
not moving. The ECM thinks the sensor is being erratic. Since
your TPS has been relaced (I think) recently, I would guess this
is the case. Also, the EGR pintle position is just another
three lead potentiometer feedback from the EGR motor position.
It also uses a +5V regulated voltage across the potentiometer.

If there are power regulation issues in the ECM, all kinds of
odd behaviour can be had from it.

Since you say you had bad luck with the replacement ECM, I
have to ask if you are certain you received the correct replacement
model. If not, the EEPROM may not have worked with it, and the
ECM would not work well with your car. Model year 1995 had 4
ECM models and model year 1996 went from OBDI to OBDII, which
are completely incompatible with one another.

Dealers have the appropriate Tech Tool scanner to completely
check the ECM, and can access built in tests which no aftermarket
scanner can. Since you have gotten to this level, I suggest you
shop around for a reputable dealer (perhaps a well established
Caddy dealer) and provide them with a clear detailed list of all of
the changes in regards to your ECM.

GuMan

dmorlow
02-19-2005, 12:39 PM
Well, here's another update on the car. I brought it to another tech a few days ago and he said when the car wouldn't start, the fuel pump wasn't turning on. So he went to Napa and bought another fuel pump, installed it and the car is running perfect now. What are the chances of that? The old fuel pump go bad to where it didn't start on random days (not going out completely), then my new pump having the same exact issue (just random days the car doesn't start). But he replaced the pump again and now it runs perfect. The part that sucks though is the company that sold me the defective fuel pump won't take it back.

jagchick
11-18-2005, 04:39 AM
I know at least a few of you guys have had trouble with yours starting. My 98 has slowly deteriorated with a starting problem. When it has been sitting overnight it starts right up. If I'm at the gas station for a few minutes it starts right up. But if I've driven it and then let it sit 2-4 hours it turns, turns, turns, but takes a few tries to start up. I don't touch the gas pedal, never have. I run premium. Took it to a mechanic, he put a new starter in it, problem remains. He said to put new spark plugs and wires in, did that, problem still remains. What were you saying about a fuse? Oh, and mechanic did a pressure test on the fuel system, it's fine. He said the pump has a small leak, but pumps up right away. I hear the fuel pump come on about 30 sec after ignition is turned, it goes off about 5 sec later. Poor college student here with no more dough to throw at the car. Please help.

Retro-D
11-18-2005, 09:02 AM
I know at least a few of you guys have had trouble with yours starting. My 98 has slowly deteriorated with a starting problem. When it has been sitting overnight it starts right up. If I'm at the gas station for a few minutes it starts right up. But if I've driven it and then let it sit 2-4 hours it turns, turns, turns, but takes a few tries to start up. I don't touch the gas pedal, never have. I run premium. Took it to a mechanic, he put a new starter in it, problem remains. He said to put new spark plugs and wires in, did that, problem still remains. What were you saying about a fuse? Oh, and mechanic did a pressure test on the fuel system, it's fine. He said the pump has a small leak, but pumps up right away. I hear the fuel pump come on about 30 sec after ignition is turned, it goes off about 5 sec later. Poor college student here with no more dough to throw at the car. Please help.

I often wonder why people allow their starter to be changed by a mechanic when the old starter is still cranking (turning) the engine? Same with the sparkplug wires, if the car has not been misfireing under load what would lead someone to believe this is part of a starting problem? If the fuel system is showing a pressure leak like (the mechanic has told you) you could have an injector leaking causing a 'flooding' condition after the car has sat awhile and leaked all the rail fuel into the intake. This could cause a long cranking senerio like you describe. The fuel pressure regulator might also be faulty.
Maybe ditch this mechanic, sounds like he wants to sell you everything but what you need to fix the car.

RD

jagchick
11-18-2005, 04:19 PM
Thanks, RD. I am not going back to this mechanic, although he has already gotten all of my money. I don't know who to go to that can work on my car at a decent price, since my dad refuses and I certainly can't. But at least this forum helps narrow down the possibilities. I never thought about a leaky injector. How hard is that to fix? And would it cause any other problems besides starting? where does the gas go when it has time to sit overnight? It obviously does not flood after it's been sitting that long. Only when it's been sitting 2-4 hours.

jagchick
11-18-2005, 04:25 PM
Oh and when I am cranking it over waiting for it to finally start, sometimes it pops through the intake. I wonder how much a mechanic charges to check for leaky fuel injectors. The only thing dad and I can work on is carburetors, if anything.

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