Diagnostic codes?

[mediocre george]

Hey everyone. Name's george, first time here, hoping someone can help me out.

My 91 Cutlass Ciera, with a 3.3 wouldn't start today. Car has 170K on it, and typically runs great. But this morning, it cranks over but won't start. I've checked it for spark, as well as fuel pressure, and they both seem good. Here's where my tale becomes frustrating. I can't find my hayne's manual anywhere. I sold a camaro several months ago, and I had planned to leave the hayne's manual for the car in it. Now, I can find the camaro manual, but not my ciera manual, and I have a sinking feeling that I gave away the wrong one

So, the car will start briefly with a shot of starting fluid, but not besides that. The fuel seems good. I haven't checked it with a gauge, but I've got enough gas on the floor of my garage now to prove that the pump's working So I'm thinking the next logical step is the ignition timing, which is controlled by the ignition module, I believe. So my question is... Can anybody tell me which ports on the diagnostic terminal I need to connect the jumper wire to in order to get the code? And can anybod tell me what code should show up if it is a problem with the ignition module? thanks in advance.

George

[BNaylor]

Welcome to AF.

See tech link below and then select your year and engine for diagnostic codes.

Click here

[mediocre george]

That link is an awesome reference, B!!

So, update on my tale of sadness. I tried to pull the codes, and ran into something I've never seen before. I couldn't get the codes, because when the key is on/engine is off, the check engine light comes on while the fuel pump is running? Never heard of such a thing. This car hasn't given me any odd electrical issues before.

But, I did get to thinking about a few things. I noticed that the car will typically start if I let the pump completely prime first. After that, if I keep the RPMs high, it will keep running, though it still has moments where it wants to stall. So I've started to wonder if I'm looking at a leaking injector?

This would be so much easier if I could pull a damn code

So, I guess my plan tomorrow is to hit the local junkyard, and pick up a fuel rail, and ignition module, try them both, and see what happens. Anybody have any last minute advice before I make the trip out there in the morning?

George

[GTP Dad]

George,

This has all the symptoms of a blocked fuel filter. When was the last time it was changed? The fuel pump should run when the key is turned to the on position. This is quite normal for fuel injected cars. The only other thing that might be causing your problem is a bad ECM. They are relative inexpensive for this model and a wrecking yard should be able to fix you up.

Let us know what happens.

[mediocre george]

GTP,

OK,changed the fuel filter, and it's running much better now. still stalled a couple times, so I don't have it quite licked yet. I'm going to drive it for a couple days, and decide what to do then. Definitly started much easier (didn't have to wait for the pump to prime before I started it), and it seemed to cure the lack of power issue.

When I was checking for a leaky injector I pulled the front 3 plugs (to see if I could find one that was fouled), and they all looked pretty crappy, so that'll be my next step.

Also, I know that the pump should run with the key in the on position... but is it common for the check engine light to come on when it does it?

[GTP Dad]

Not really. The issue may be ECM related as I said before. Since the ECM sends a signal to the injectors that may be the culprit. You may want to check with the local wrecking yard you should be able to pick up a good one for about $25. The only way to eliminate that is to give it a try especially if the cel goes off after the engine starts. On the OBD1 your diagnostic ability is quite limited and even if you can pull the code it may not be enough to remedy the problem.

[mediocre george]

Argh... So, I changed the fuel filter yesterday (man did those clips make life easier than using steel lines!) and it started right up, and ran fine, though I only drove it a few miles to work. Then at the end of my shift, it started right up... and died within about 2 minutes, and wouldn't start back up. So, I walked home from work (AGAIN!!). Alright, so I guess next stop is an ECM.

[JohnDD]

To get the error codes to show up on the Service Engine Soon light, just use a paper clip to short pin A to pin B on the diagnostic connector (top RH pin and to the left of RH). Then turn the key to ON. Should flash "12" three times, then any error codes after that.
johndd in Ottawa

[mediocre george]

Yeah, that's what I'm doing john. It's not flashing 12, or anything for that matter. I haven't done anything with it the past few days. Got some other stuff going on.

[Ian Szgatti]

Originally Posted by mediocre george

Yeah, that's what I'm doing john. It's not flashing 12, or anything for that matter. I haven't done anything with it the past few days. Got some other stuff going on.

fuel pump. Even though you can hear it, its. not up to par. Change that, you'll be good to go. Get one that has been bench tested for flow rate and vibration.

For fun try this, detach the vacumme hose from the fuel pressure regulator... given your pump cannot provide enough fuel pressure in the rail, I suspect it will start with the increase in pressure, and then stall shortly after. Even without such a test though, or despite the outcome, I can assure you need a fuel pump. Unfortunately, you will not get any codes. This is a purely mechanical issue.
Heres a trick for you, when in doubt about spark related problems, connect a halogen headlamp to the spade terminals that mate the DIS modual to the coils. If the lamps flashes when the engine is cranked, the Crankshaft Position Sensor and modual are ok, and the problem is in the coil(s).

[mediocre george]

Wow, finally got it figured out today. After checking the injectors for pulse and finding none, I decided it HAD to be an issue with the ECM, despite having already changed it. A wiring diagram, test light, and half an hour later, I found that there was no power going to the ECM, despite there being power at the fuse. Ran a wire from the fuse panel to the ECM, and now it's golden

Thanks for all the advice, everyone.

[Ian Szgatti]

What was the condition of the wire? was it due to corrosion? I am wondering whether the resistance values of the injectors are at all to blame with current through the circuit effecting that wire...
For example, 12 volts divided by 6 ohms equals 2 amps.. 12v divided by 2 ohms equals 6 amps. yeah, a fuse still protects the system, but a degraded wire wouldnt be able to handle its regular load.. just curious as to the condition of the wire itself.

[mediocre george]

I'm assuming it must have been corroded, though I couldn't find a spot that seemed bad. It certainly wasn't severed, and it seemed to make good connection at both ends.

[mediocre george]

I'm assuming it must have been corroded, though I couldn't find a spot that seemed bad. It certainly wasn't severed, and it seemed to make good connection at both ends.

[CL8ON'S FIORD FIXM]

try the top 2 slots on the aldl with a jumper wire