Major Trouble Codes

[GreyGoose006]

Ok, so occasionally i get a check engine light while i'm driving. usually once the car has warmed up.
the other day, i decide to check the codes on the ECM and heres what i find:
13
14
15
23
24
25
26
32
35
43
44
45
52
54
...
i didnt go any farther, but from what i can tell, nearly all my sensors are failing, namely the EGR, O2, and BARO, my engine is running both rich, lean, hot and cold.

WTF???

[MT-2500]

Originally Posted by GreyGoose006

Ok, so occasionally i get a check engine light while i'm driving. usually once the car has warmed up.
the other day, i decide to check the codes on the ECM and heres what i find:
13
14
15
23
24
25
26
32
35
43
44
45
52
54
...
i didnt go any farther, but from what i can tell, nearly all my sensors are failing, namely the EGR, O2, and BARO, my engine is running both rich, lean, hot and cold.

WTF???

Clear codes and see what comes back.
And post back no.
Usually with that many codes you have a internal pcm/computer problem.
MT

[Blue Bowtie]

Agreed. Clear it if you can, and scan again. Reseat the PROM if you can. Verify ECM and engine wiring harness grounds.

Is this on the '84?

[GreyGoose006]

thing is, i cleared it about two months ago when i got this many codes.
the "normal" codes i get are rich condition (45) and O2 sensor failure (i believe 13)...
the car runs fine, with the exception of a bit of hesitation, and backfiring when you stab the gas.

[MT-2500]

Originally Posted by GreyGoose006

thing is, i cleared it about two months ago when i got this many codes.
the "normal" codes i get are rich condition (45) and O2 sensor failure (i believe 13)...
the car runs fine, with the exception of a bit of hesitation, and backfiring when you stab the gas.

Clear codes again and see wha one or ones come back first.
But.
With that many codes I would go for a rebuilt or used PCM.
MT

[silicon212]

I second MT2500 and Blue Bowtie about it being ECM related - however before springing for a new ECM, do check your grounds throughout the ECM wiring harness and ensure they're all good. When I got my car in '02, one of the ECM grounds to the intake manifold were broken, and I was getting codes much like yours (including 55, the "dead ECM" code). After finding and fixing the ground, I can honestly say that more than 4 years later, that "dead ECM" is trucking along nicely. I will get the occasional Code 45 telling me that it's been more than three months since I changed the air filter (I live in a DUSTY area) or that the $#$&@&*# choke heater wire fell off again, but that's about it. Blue Bowtie touched on the grounding issue.

[capriceowns]

My caprice runs very rich ever since I rebuilt the carb, would it running rich trigger a Serive engine soon light? or will it just tell me that its rich when I scan it.

cause I got no service engine light, idk if it works. I m sure it does, its on when I turn the key and goes off after the car is running.

[silicon212]

Originally Posted by capriceowns

My caprice runs very rich ever since I rebuilt the carb, would it running rich trigger a Serive engine soon light? or will it just tell me that its rich when I scan it.

cause I got no service engine light, idk if it works. I m sure it does, its on when I turn the key and goes off after the car is running.

For the heck of it, check for trouble codes. If you get a 12, then your system is working. If it is working, and it's not tripping the SES light, then your carb is not running rich - unless the EGO sensor is marginal. If it really is running rich, the ECM and EGO sensor both working, it should set a Code 45 and light up the SES light.

[GreyGoose006]

yeah, if its rich it will pull a code 45, and maybe 13 if it is really bad.

i forgot to mention that i do get a code 12 at the start and finish of the codes.

i'll clear them now, i have a long drive (about an hour) ahead of me today, so if any come back, ill know they are the real problem.

side note,
there is a green plug in my engine bay that is not connected to anything, it is the female end and there is nothing to connect it to...
i've showed it to my uncle (electrical engineer, he knows more than most people that he brings his car to to have it worked on) and he dosent know what it is. it looks kinda like a hack job, where someone put it in themselves...
if anyone has any insights i would appreciate it

[silicon212]

Originally Posted by GreyGoose006

yeah, if its rich it will pull a code 45, and maybe 13 if it is really bad.

i forgot to mention that i do get a code 12 at the start and finish of the codes.

i'll clear them now, i have a long drive (about an hour) ahead of me today, so if any come back, ill know they are the real problem.

side note,
there is a green plug in my engine bay that is not connected to anything, it is the female end and there is nothing to connect it to...
i've showed it to my uncle (electrical engineer, he knows more than most people that he brings his car to to have it worked on) and he dosent know what it is. it looks kinda like a hack job, where someone put it in themselves...
if anyone has any insights i would appreciate it

That's a diagnostic port for the carburetor - hook a dwellmeter to it, and you can adjust/check the M/C solenoid.

[kdrolt]

Clean the terminals at the battery.

Make sure you have the brass-colored stud near the underhood fuse/relay box (near the firewall, pass side on a 94-96 car).

Low battery voltage makes the PCM do some wierd stuff an set bogus codes.

[silicon212]

Originally Posted by kdrolt

Clean the terminals at the battery.

Make sure you have the brass-colored stud near the underhood fuse/relay box (near the firewall, pass side on a 94-96 car).

Low battery voltage makes the PCM do some wierd stuff an set bogus codes.

1984, not 1994.

[kdrolt]

Originally Posted by silicon212

1984, not 1994.

Oops. My bad. Sorry.

[GreyGoose006]

update...

i pulled the codes after the first part of the trip. the only code that came up was 45 (aside from code 12 at start and finish)
interesting to note that on the way back, the check engine light did not come on as usual on the highway. i'll check the codes tomorrow, but i'm too tired now.

is it possible that there is something catastrophic about to happen to my engine, and the computer isn't crazy? the rason i ask is that after driving for an hour, and letting the car cool down for 3-4 hrs, when i started it back up, it made a wierd tapping noise when put into drive. not in neutral, park or "1".
it was there in drive and there was a hint of a noise in "2".
to me, it sounds like a collapsed lifter, or something knocking around in my cam/head region.

HELP!!!

[silicon212]

Originally Posted by GreyGoose006

update...

i pulled the codes after the first part of the trip. the only code that came up was 45 (aside from code 12 at start and finish)
interesting to note that on the way back, the check engine light did not come on as usual on the highway. i'll check the codes tomorrow, but i'm too tired now.

is it possible that there is something catastrophic about to happen to my engine, and the computer isn't crazy? the rason i ask is that after driving for an hour, and letting the car cool down for 3-4 hrs, when i started it back up, it made a wierd tapping noise when put into drive. not in neutral, park or "1".
it was there in drive and there was a hint of a noise in "2".
to me, it sounds like a collapsed lifter, or something knocking around in my cam/head region.

HELP!!!

A quart of ATF in the engine in place of a quart of motor oil will help to loosen up stuck/collapsed lifters. It will also de-sludge the engine, so you will want to change your oil and filter in one full gas tank of running - expect to see tar-black oil come out.

I don't think your engine is about to bite it - but if the tapping noise only happens in certain transmission ranges, then you might want to look into the transmission itself.

A Code 45 can be caused by a failure in the carburetor, or simply a plugged air filter. Remember that green connector that you were asking about? Now's the time to use it. Get a dwell meter, set it to the 6-cylinder range, and start the engine up - hooking the dwell meter positive to that green connector and the negative to ground. Look at the reading - normal range is 25-35 degrees. If it's less than 25, you're running too lean at the M/C solenoid and if it's higher than 35, you're running too rich. If it reads normal, and you have a new/clean air filter, then suspect a bad EGO sensor.

Running the car excessively rich for extended periods will destroy both the EGO sensor and the catalytic converter.