93 Astro van problem

I've got a 93 astro that has 15k on a replacement(new) engine. Everything was absolutely great for the first 18 months(apprx.) the new engine will have been in the van 2 years in November. Anyway. One morning I go out to start it to go to work. and it takes a few seconds to start(this is from an enging that usually fired up as soon as your hit the key), and after it started the check engine light stayed on. I got to my first stop, where I stayed 5 monutes or so, and when I started it to leave, everything was perfect again(no check engine light either). This didn't happen again for a month or so, and it did the same thing(exactly). Since then it has started doing it more frequently, and actually becoming harder to start the first time also, but check engine light goes off after it's stopped somewhere, sits five minutes and cramked again. Last week it did the same thing, only this time it just wouldn't start at all on it's first start of the day. Had to let it sit 15 or 20 minutes, and it did then start. Afterwards; no problems again. It has never done this except on the first start of the day; until today. It did it this morning, and then did it again when I got off work. I took it to the shop I use, and there was a code history for the fuel pump, but they were unable to duplicate the problem, and didn't do anything. They said they would have to trace it down as it might not be the pump but a relay, or something other fuel pump related. My questions are; If it was a bad pump, why would it eventually start up, and run fine? And, what do any of you think it could be. I had new injector kit put on when the engine was replaced. Thanks.
John Sr.

hello are you capable of pulling codes??if so i would wait until ses light is on
then see what codes are stored.you'll probally get a fuel system code.need to be able to do leak down test,ck for proper fuel pressure etc.

It could be the pump or the relay causing the SES to be set. Get the codes, all you need is a paper clip, and come back with them.

Thanks guys for the quick responses. I just went out to the truck before I check for post replies to start it to see how it did, and it fired right up just as pretty as you please. It seems to be only after the van has set for the day, or overnight; that the problem occurs. CD; what do you mean "all I need is a paper clip to get the codes when the check engine light is on"? I don't have a code reader myself. Also; what is a worth while code reader to purchase, and what do the usually cost, and are they hard to learn to use? Thanks so much guys. I'm in a spot now where I just don't have the money to pay a shop to chase down the problem except as a last resort.
John

I've been trying to look at OBD code readers on the internet, as I guess it's time to get one, and I unfortunately see that most for sale are OBD 2 models, and they won't read anything except 1996 and later model cars. I see a few OBD1 models but man do they look primative in comparrison to the OBD2's. I'd like something that will reset the CEL when it comes on too. What do you recommend? How do the ODB 1 and 2 models do? Do they give you all the options with 1995 and older models that they give you with 1996's. It looks like the 1 and 2 version is the one to get. What model do you guys use for 1995 and older models cars/trucks/vans?
Thanks again.
John

Your mechanic is feeding you a line. Fuel pump and fuel pump relay problems cannot set DTC's or turn on the SES on OBDII much less OBDI. Find out exactly what codes were set and post them here. Your system is an OBDI and retrievable data is minimal. Code readers for OBDI are available at most auto parts stores, even Walmart has them... very inexpensive and easy to use.

How do I read my computer codes? NOTE - This is a work in progress!!!!!

Tools needed:
Your car keys
A paper clip or a three(3) inch long piece of safety wire.

First thing you need to do is find your Assembly Line Diagnostic Link or ALDL. It s small black plastic piece about two (2) inches wide by one half(0.5) inch tall. It has twelve (12) female connector inside. The ALDL can be found under the driver's side of the dash, usually attached with two (2) screws to the bottom side of the dash.

The ALDL :
Now that you've found the ALDL, bend the paper clip or the piece of wire into a U shape. With the ignition in the OFF position. Insert one end into the A slot and one into the B slot. Now turn the the ignition to the ON position. DO NOT start the car. As the ECM begins it's self-test if will begin to flash the SES light to provide the codes. The flashes will appear like this : *flash* short pause *flash* *flash* long pause then repeat. Each code will be displayed three(3) times. Code 12 will be repeated to indicate the end of the set codes. If you all you get is Code 12 then you have no codes set in your ECM.

An example of a sequence for a common code :
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM


Clearing the codes is really quite easy. Unhook your battery for about 2-3 minutes and then hook it back up.

These codes cover the OBD-I computers only.....
All currently listed codes are from the 1989 B-car Service Manual. Why? Because that's what I have. If you have others that aren't listed or need to be added, just let me know.


CODE AND CIRCUIT POSSIBLE CAUSE

CODE 12 = System check
Indicates that the ECM is functioning.

CODE 12 = No Engine Speed Reference - VIN 'Y' CARB
Indicates an open or ground in the distributor reference circuit.

CODE 13 = OPEN Oxygen Sensor (O2)
Indicates that the oxygen sensor circuit circuit or sensor was open for one minute while off idle.

CODE 14 = Coolant Sensor (CTS)
Sets if the sensor or signal line are grounded for 3 seconds. HIGH Temperature indication.

CODE 15 = Coolant Sensor (CTS)
Sets if the sensor wires or connections are open for 3 seconds. LOW Temperature indication.

CODE 21 = Throttle Position Sensor (TPS)
TPS voltage of more than 2.5 volts for 3 seconds at an engine speed less than 1200 rpm. HIGH Voltage Signal.

CODE 22 = Throttle Position Sensor (TPS)
A shorted to ground or open signal circuit will set code in 3 seconds. LOW Voltage Signal.

CODE 23 = Manifold Air Temperature Sensor (MAT)
Sets if the sensor wires or connections are open for 3 seconds or Intake Air Temperature (IAT) LOW Temperature indication.

CODE 24 = Vehicle Speed Sensor (VSS)
No vehicle speed present during road/load deceleration. NO Vehicle Speed Indication.

CODE 25 = Manifold Air Temperature Sensor (MAT)
Sets if the sensor or signal line are grounded for 3 seconds. Or Intake Air Temperature (IAT)
HIGH Temperature indication.

CODE 32 = Exhaust Gas Recirculation (EGR)
OR Vacuum switch shorted to ground on start up. Switch not closed after the ECM has commanded EGR for a specified period of time OR EGR solenoid circuit open for a specified period of time.

CODE 33 = Manifold Absolute Pressure (MAP)
MAP sensor output too high for 5 seconds or an open circuit. LOW Vacuum.

CODE 34 = Manifold Absolute Pressure (MAP)
Low or no output from sensor with engine running. HIGH Vacuum.
CODE 35 = Idle Air Control (IAC)
IAC error.

CODE 42 = Electronic Spark Timing (EST)
ECM has seen an open or grounded EST or Bypass circuit.

CODE 43 = Electronic Spark Control (ESC)
Signal to the ECM has remained low for too long or the system has failed a functional check.

CODE 44 = LEAN Exhaust Indication
If voltage to oxygen sensor remains BELOW .2v for more than 20 seconds code is set.

CODE 45 = RICH Exhaust Indication
If voltage to oxygen sensor remains ABOVE .7v for more than 1 minute code is set.

CODE 51 = PROM - Faulty MEM-CAL or ECM.

CODE 52 = Faulty or missing CAL-PACK.

CODE 53 = System overvoltage
Indication of a faulty alternator or regulator. Camaro/Firebird uses a Code 53 for Vehicle Anti-Theft System (VATS).

CODE 54 = Low Voltage To Fuel Pump
Sets when the fuel pump voltage is less than 2 volts when reference pulses are being received.

CODE 55 = Faulty ECM


johntheson - That's how with with a paper clip.

OldMaster - see Code 54, the above is straight from the 89 B-Car factory service manaul. I also found the same code listed in my 1992 Astro Van factory service manual.

CD,
Please forgive my ignorance; but with the papaer clip method; wher are the codes displayed at? On the istrument panel? You refer to the ECM doing it's test; I assume that the ECM must be the onboard computer? Thanks everyone. Is the OBD1 worth buying? Does it provide enough info to make it worth the purchase? Also;if your replies are that the OBD1 is worth buying; I will stop at Walmart on my way to work in the morning, and I'll post the codes when I get home. I am grateful to all of you.
John

As it says above, the codes are displayed by the flashing of the SES light.

OBDI code scanners are pretty much worthless unless they are reading real-time data. I'll see if I can find a picture of the ALDL for you. It will be much clearer then.

Most of them are nothing more than a nifty package around something like this:

http://www.toolweb.com/pics/LIS22700.jpg

Here you go:

http://www.metzcon.com/racing/images/ALDL.jpg

Thank you CD. I understand now what you are trying to help me see. For some reason or another, the older I get (54 now), the harder time I have processing what I'm reading. If I live to be an old man, I may need directions for tying my shoes. Again. Thank you all.
I'll post the results.
John

No worries John. A picture is worth a thousand words you know. I know I need them too, more often than I would admit.

CODE 54 = Low Voltage To Fuel Pump
Sets when the fuel pump voltage is less than 2 volts when reference pulses are being received.

OldMaster - see Code 54, the above is straight from the 89 B-Car factory service manaul. I also found the same code listed in my 1992 Astro Van factory service manual.



That's correct, but that's as far as it goes. Don't read more into it than it says. "Low voltage to fuel pump" means exactly that. Each time the key is turned to the RUN position, the ECM does a self test. If it detects low voltage is being sent to the fuel pump relay, DTC 54 is set. The purpose of the DTC is to let you know the ECM is not supplying power to the fuel pump relay, (which in turn supplies power to the fuel pump). There are no provisions for the ECM to monitor the fuel pump, or fuel pressure, so they cannot set a DTC if they are faulty.