What Else to try (START/RUNNING ISSUES)

Car fails to start (99% of the time). 94 camaro l32 v6. NO ALARM

Issue began 3 weeks ago: Leaving work, initial crank > Car fired, hesitated...put put, off. Tried several times untill finally it remained running. Ran Fine.

Got home, .5 hour later tried to turn back on, It fires, put putts and shuts down.

Wires are no more than 30K miles, I removed plugs (Carbon fauled). Decided to replace. New plugs fired up... Ran good. Turned off and back on a few times, no problems. (I was happy.. cheap easy fix) About .75 hours later same thing, back to square one (and upset) Car would fire, but will not stay on.

Since then: GOOD SPARK. (Coils changed for the hella of it, time for tune up I suppose)
ICM has been tested at autozone, Passed.
MAP sensor replaced
FUEL PRESSURE READ at 42PSI (More on this later)
NEW FUEL FILTERS
24X Crank shaft position replaced.
3X has not been changed, (I changed 24X because water pump was leaking all over it).
IF I remove 3X, car will not even fire... It will just crank.
Injectors have voltage, I am not sure if they are pulsing or not but there is a FUEL pressure drop of about 8 PSI when It fires thus making me think they are.

FUEL Pressure regulator is not Leaking, and from what I can tell is working. If I apply Small vacume FUEL PSI WILL DROP. Will Come back up when Vacum is released.

******** CAR WILL STAY ON AS LONG AS Starter fluid is sprayed in throtle body ****** and due to this reason many suggested to replace Fuel PuMp... WELL, I have and same problem. Very rare cases the car will keep running by itself, this has me confused as if the injectors would be clogged it would never turn on right (without spraying starter fluid down TB). I was hesitant in replacing the pump as the PSI was reading okay, ALso when car was running with Starter liquid, I released pressure and it would stay at 20 or so psi. Pump was running.

I have had some mechanics look at it, but it does not appear they are very good or get scared when you tell them everything that has been done. I have done all of the above work and pump was a real Pain! (especially for it not to have worked). At this point I am almost thinking of just getting a STANG. NOOOOOOOOOO... but then again I need the upgrade (this is only v6).

I look forward to some real advise! Hopefully I can finally get the car up and running, 3 weeks is a long time! O, 40k miles ago, headgasket replaced, heads cleaned/resurfaced..etc.

The only thing I can think of is that it is not getting gass, but why I do not have any clue.

...........plugs (Carbon fauled). Decided to replace. New plugs fired up... Ran good. Turned off and back on a few times, no problems. ......... 0.75 hours later same thing, back to square one ........GOOD SPARK............. CAR WILL STAY ON AS LONG AS Starter fluid is sprayed in throtle body..........Take another look at the plugs. If they are fouled let us know.If they are not have a friend try to start the carwhile you observe down the throttle body with a POWERFUL flashlight.Use wheel chocks and watch out for moving parts!
See if the injectors are spraying. (we're assuming it's a TBI setup). This will steer you in the right path..§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§REFUSE . . TO . . LOSE§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§

NINÅ:
we're assuming it's a TBI setup
A: actually the L32 is not that bad... It uses MPFI Injection, but of course that will make it harder to see. How would you suggest to check if they are indeed injecting? Also, the car is at least getting the initial spray as it does fire... Would this be correct?

Take another look at the plugs:

A: they continue to become fauled. At first I thought it was running really rich, but the only way it will stay on is if I spray down the TB. I does not add up. To farther complicate my thinking I have no IDEA why 2 or 3 times it has started with out the need of starter fluid.. Any Ideas... Please advise if my assumptions are wrong. So far they have been :0)

Is the engine light on at all when the car does run? Try pulling the error codes..

Also, about the poll.. I highly doubt this is the fault of the computer.. I very rarely see problems with a bad pcm..
When you check the plugs, are they all in the same condition? are they all fouled equally? If so, than I wouldnt think you would have a problem with your injectors either.. I would lean more towards a faulty FPR

Is it possible someone poured something into your gas tank while your car was at work??

Is the engine light on at all when the car does run? Try pulling the error codes..

Also, about the poll.. I highly doubt this is the fault of the computer.. I very rarely see problems with a bad pcm..
When you check the plugs, are they all in the same condition? are they all fouled equally? If so, than I wouldnt think you would have a problem with your injectors either.. I would lean more towards a faulty FPR

Is it possible someone poured something into your gas tank while your car was at work??


Unfortunately no check engine light. When the car is on and working it works. the initial day, I stepped on the gass to ... "CLEAN" everything out.

As for the Gas, HUM... It could only have happened at time of refulling (it has a key). Bad batch of gass maybe? Now that you mention it some news storries reported some bad bathes of gass (couple months ago). Different brand, but now that you say that and now that the tank is just about empty I will put in another 2.5 g of fresh fuel.

Keep fingers crossed. Man, I just thought of something... We added the fuel to other cars as I was draining the tank yesterday. LOL, I sure hope nothing happens or there goes all form of transportation!

Unfortunately no check engine light. When the car is on and working it works. the initial day, I stepped on the gass to ... "CLEAN" everything out.

As for the Gas, HUM...

....LOL, I sure hope nothing happens or there goes all form of transportation!


Looked at the gages, and even when it tries to turn and in the process of trying no check gages or service engine light will be on. They do turn on, but as they normally would turn off.

Well, Tried the new gas on a prayer same results. Tried about 10 times all with same results. Engine fires, tries to stay running, shuts down. Sometimes when pressing gass slightly or floored it will try harder with the ocasional HIGH REV (no stutter) and SHUTDOWN. Also, I can turn the key again with out turning off and then back on. NEW Pump is working.

Guess other cars have nothing to worry about.. Whew.

I will take out the plugs (again) tomorrow, possibly buy another cheapo pair just to see if it was a crazy coincidence or not.

More info on plugs: Day one, when I removed the bosch Plats they where all the same. When I bought cheapo pair after initial run not certain. But after repeated attempts ALL are fouled. If the car does turn on tomorrow with new plugs I will let run, shut down and view plugs.
Cleaning plugs does not seem to help...

..............another look at the plugs:
.....they continue to become fauled.........Carbon is a conductor, therefore carbon fouling shorts the plugs, result: little or no spark. Make sure the plugs are the proper heat range. It won't hurt to try a "hotter" range plug to help you pinpoint the problem. Starter fluid (ether) is capable of dieseling much easier than gasoline which explains why it can run with no spark..§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§REFUSE . . TO . . LOSE§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§

Carbon is a conductor, therefore carbon fouling shorts the plugs, result: little or no spark. Make sure the plugs are the proper heat range. It won't hurt to try a "hotter" range plug to help you pinpoint the problem. Starter fluid (ether) is capable of dieseling much easier than gasoline which explains why it can run with no spark

Well, that makes sense. Well, it made sense at first. Maybe I am over analyzing but here is what I mean: When I say the car continues to run, I don't mean dieseling. I mean it continues to operate (at least I thought it did :0)... now I am really lost. I am sure the plugs are getting spark under this condition, granted I do not know if it the other end of the plug is strong enough. I am also sure that in this condition the pump is still running because on prior Trouble shooting I opend the release valve from the Pressure Gauge and gas did drain (to approved Gas Container). The pump remained pumping until car was turned off via switch. I know the injectors had voltage in this condition as well. Car was missing but then again I also had one injector disconnected to test for voltage. Unfortunately I was using an old analog voltage display so could not determing if pulsing or not. Could not find a noid light. Father had a test light, burned out an injector fuse. Got scared, did not try again!

As for exhaust gas if it helps: Rich

Question for ya: Theoretically if the above is all true, Once I got the car to fire, do you think the gass would not continue to ignite???
I really do want to find out what will happen tomorrow! Thank you so much for the great brainstorming and suggestions. Please keep them comming.

<EDIT> <EDIT> After more thinking, The car will always have enough spark to at least fire the car with normal gass, no spray. This is a constant. If the plugs are that badly fouled, would this be typical? When I say the plugs are fouled I don't mean there is carbon forming a bridge. There is a light covering over electrodes.

Sorry for the newbie question, I just don't know :0).


... to much brainstorming... must stop. Can not go farther. Seriously, thanks to ALL. Will let you know what occurs with new plugs.


EDIT: MONDAY. Well, I tried the new plugs, NGK UR5 model 2771. Interesting enough it did not turn on. Must have been coincidence on the first set of plugs i changed. With the new plugs, did not stutter as much. Old plugs were all the same, they also had Fuel left over from last night (wet). Should they have been? Below is a link compairing old to new plugs (after 10 cranks/attempts)

http://www.geocities.com/wiriza01/Sparkspic1.JPG

As per earlier suggestions I will check regulator a bit farther now.

As per earlier suggestions I will check regulator a bit farther now.



Well that just sucks.. Regulator is not serviceable (torx like screws but on center it has a pin. Tool has to be hollow). Manual indicates there are some 3rd party kits, but I could not find any. Injectors look clean and resistance on each passed. If it turns out to be the regulator any one know where to find the rebuild kits?

http://www.geocities.com/wiriza01/Injectors.JPG

The only thing left is that 3x crank shaft position sensor. (GM part manual indicates it as 7x cr position sensor PN: 10456108). I will also replace the cam shaft position sensor, as well, however the cam shaft should not be a factor as the PCM should run defaults if it does not get a signal.


DaMoNe6969:

I have good old 12 pin diagnostic port, prior suggestions got me curious if anything will show up so I tried to jump 5/6 but no flashing of lights. I have done this before (different cars, really liked Lebaron so easy to self initiate codes). and puzzled as to why nothing, no flashing, not even code 12. I checked pin 6… good ground. I do have a question I came across. Not sure if manual or online but if you ground pins and turn car on is it true that it will be running in “safe mode” with PCM running at default values?

The only thing left is that 3x crank shaft position sensor. (GM part manual indicates it as 7x cr position sensor PN: 10456108). I will also replace the cam shaft position sensor, as well, however the cam shaft should not be a factor as the PCM should run defaults if it does not get a signal.


finally changed position the second crank shaft position sensor. Car fired. Turned on, stayed on. turned the car on a few times and all seemed good.

Drove it some more, came to a stop > car shut down. at this point I cranked it again, it turns on now... just won't idle for more than 2 minutes. It is odd, because when I first cranked it, cold it was running fine.

Anyway, gonna check tps and ais. At least it is turning on now.

ALSO, the check engine light is on, I tried to jump codes again would not flash them.

EGR cables seem to have become damaged with all the removal the last couple of days, as if I move cables while car is on it will miss and show above issues. Well, for those out there with similar issues do not forget to test/change the 3x position sensor

94 should still be OBD1. you said pins 5 & 6... are they the upper RH 2 pins? (A & B on most GM ALDL's) Jump them key on engine off should give up the codes.

94 should still be OBD1. you said pins 5 & 6... are they the upper RH 2 pins? (A & B on most GM ALDL's) Jump them key on engine off should give up the codes.


Yup, I jumped upper rh 2 pins and it is not giving me the code. the top row has 6 pins, bottom has 6 pins total of 12. It should be odb1.

p.s. I am back to square 1. Today I went to turn on the car and recieved the turn on and stop running deal. this is getting crazy, why does the car not like me anymore????

Well, I hate to say it but if the check engine light works and the ECM won't give codes..it usually means the ECM is bad...can you borrow one to confirm this?

Funny thing is I want to take it or have a worthwhile mechanic look at it but at this point what for :0).



Anyone know of a good mechanic in 33193... LOL. Guess what happend.

Well, I got test computer and here goes.

First I attempted to turn car on with original computer. Would not stay on...
I need to put knock sensor on test computer, hook up computer. Fire it up and it is running. I am like Yes!
Like anyone else here, I then disconnect, swap knock back to original. hook up original and attempt to start it up. Guess what happend... IT FREAKEN FIRED UP AND STAYED RUNNING... At this point I think the car is just messing with my mind.

On a side note: checked for codes w/ test computer and it will not flash the code either. Must be a year thing? The manual indicates it may not be possible even though it has a 12 pin diag port. Anyone out there have a 94 l32 engine that they can test for codes?

Well, I got test computer and here goes.



Okay, so after much testing I am happy to say my computer is functional. both computers demonstrated same issues. I do think that changing the crankshaft position sensors corrected the primary problem.

Secondary problem now seems to be the idle related. Sometimes the checkengine light is turning on, but will turn off. Sometimes the Car (when turned on) will idle between 1.2 - 1.85 RPM ( X 1000) but when the check engine light turns on and then back off it drops down to correct idle. It was working like that for most of the day until after 3 hours of driving around off for about 2 hours. When I turned on, it was high idle and stayed that way. I retarted idle and well it is kinda back to normal. More testing required but at least We know it is not the computer. Any ideas if the problem comes back?

TP Sensor has been changed.