Drylar

OK. The fricking board logged me out for no apparent reason while I was typing, and lost my last post before adding it. Nice. Ok... Here goes again...

I was driving around most of yesterday without a problem. I went home, took a nap for work, went to take off and had difficulty starting my car. It acted liek it wasn't getting enough gas. I got it started, and took off. 5 minutes later, all hell broke loose. It felt like it was stalling, RPM's stayed up, it sputtered and lost all forward power. I pulled off the side, and at idle, the problems went away. I took off again, and it happened the moment I hit the accelerator. I attempted to tap once on the accelerator to see what'd happen, and it nearly flooded the engine. I could feel 'popping' in the exhaust. I didn't repeat the procedure. I limped it at a near idle to work, and let it sit. I checked error codes before taking off again, and saw 21.33,45,54 were set. I had had my battery out a few days prior and used it in my brothers boat, and charged it back up before putting it back in, so know the battery should be fine, and that there wasn't any error codes prior. As per condidtion of the electronics, the alternator and battery are less than 2 months old, the starter is 6 months, just (within the last month) replaced fan relay and fuel pump relays. O2, TPS, MAF, and Oil Pressure sensors were replaced about 6 months ago, and the ones needing tuning were 'retuned' about 2 months ago. Full spark plugs and wires 4 months ago, and about the same time, took it to get serviced for the alternator not putting out and they only had to replace the 1 wire leading from the alternator back to the firewall, and it had somehow been cut half way back. As per what else was done, at the time I got it serviced, I had them replace all of the fusible links and check all grounds. This car has been a major project to me, as I'm only keeping it to fullfill a promise made to a friend (Gonna let him see it fully restored, if I can. It was his baby, which he wanted to restore, but so much was wrong with it, there was no way he could restore it enough to drive it to his new place out of state. So he gave it to me for free, under the promise I try to restore it.) Needless to say, I've replaced ALOT on this car, and would very much like to get over this stupid electrical problem. This is pretty much all that's left in the way of how it runs (this has happened a few times before, but never to this extent). This is by far the worst it has been, and first time to set error codes.

Any help is most appreciated, and I apologize for length.

Thank You
Drylar
85 Iroc Engine 'F' 305TPI

Vader

Don't apologize. The more information you can provide, the better.

And I've had the same thing happen, but usually it's my ISP that disconnects me for "idle time" rather than the board logging out the user. Since I DON'T use AOL, my Netscape browser window remains open and I can pick up where I left off without losing data. If you've noticed, I can get some pretty long posts and replies myself. Having to re-enter all of that would be a significant PITA, (almost French).

And you get to take a nap for work? That must be a "tough" job...

O.K. Enough with the jacking around, and on to your problem.

Fortunately, you're getting error codes to help diagnose the problem. Getting data streams from the older ECMs ('85 and earlier) is not that productive due to the slow output.

Given all your stored codes, I would guess that you don't have a sensor or operation problem with the engine itself, but an electrical problem with some of the sensors and inputs. The '54' (Low fuel pump voltage - Below 2.0 VDC) almost clinches it for me. Any one of those error codes alone would indicate a possible sensor or operational problem, but since they are so unrelated, I'm guessing you have a power distribution or ground issue. I'd start by verifying a goos ground at the ECM itself, as well as the negative battery and body connections. Pay close attention to the ground node near the battery, the ground strap from the right rear head to the body, and the battery cables themselves. Since you recently disturbed the cables to remove the battery, I'd also suspect corrosion at one of the smaller wires attached to the main battery cables.

Obviously, you'll need a reliable ohm and voltmeter to help diagnose the problem. You may also be able to "cheat" by using a jumper wire between suspected bad grounding points. Clip one end to the battery negative, and the other to the chassis, engine, ECM ground harness, etc.

Another thing that may have problems is the 5 VDC supply from the ECM. You can test the reliability of the 5V supply by metering the reference voltage at teh TPS, CTS, or another sensor harness. The TPS is fairly easy, since both the +5 VDC and ECM signal ground are in the connector, as well as the TPS signal connection. You should get a straight, regulated 5VDC across the 'A' and 'C' terminals, probably gray and black wires on your car.

Good luck.