Engine wiring harness replacement - FIXED!!!!!!!!!!!!!!!!!!!

[92turboLE]

Sorry for the novel in advance.

 

Ok, so i know a lot of you kinda look down on me for events that happened in the past, but thats all said and done (mostly) and will be history very sooon, but i seriously need some help and would like to stick to the topic at hand please.

 

HISTORY:

I made a post a while back about an electrical problem with my car. Basicly, it would cut out on me (loose electrical power) at random times, and occasionally loose all electrical power (except for dash lights) and stay with no power for about 10 minutes, then just turn back on and be fine.

 

well, i was thinking that maybe it was bad plug wires, arching or shorting to the block and sending heavy feedback through the system, so i changed plugs and wires (and found out that i had ORIGINAL OEM 12 yr old plugs and wires) but that wasnt the problem. The car ran much smoother after that but the problem still prersists.

 

Yesterday i went to Laramie to meet with Josh (malibuolds) and the car did goo going up there, but coming back down, i had to pull over 5 times due to the car completely shutting off. Today has so far been no different. It is nearly undriveable. It dies about every 15 minutes of driving.

 

Anyway, i cant make it do it. There is no particular condition or action that causes it. It does it whenever it feels like.

 

finally, as i was pulling back into the parking lot at work after running some arrands, it died again, but this time after it started up again, it threw a code. well, 3 codes to be exact.

 

Code 42: Electronic Spark Timing (EST) Circuit

 

Code 44: O2 Sensor (Too Lean)

 

Code 45: O2 sensor (too rich)

 

THE PROBLEM:

The car had no stored codes before today so all three of those happened this morning or last night.

 

In the ECM code page on w-body.com, it says that each has its own cause, but all three also have a commonalities, The Wiring and possible ECM going bad.

 

For the O2, the problems are listes as possible O2 failure, but the O2 is brand new and i have also put in my old one and still no difference. so i doubt the sensor is going bad. Which leads me to believe that the wiring is going bad.

 

i have had wiring problems in the car before (corroded plugs and such) and the wire is very brittle (if you bent it too far, it BREAKS.

 

i am taking the day off tomarrow to try and fix this problem, so i am going to pull a complete harness out of a low mileage 3.1 as well as a new ignition box and coilpack, and possibly a new ECM. If none of those are the problem then i can take them back and get a refund so im not too worried.

 

What i am worried about is how hard is it going to be to remove the ENTIRE IN-TACT harness from the car without pulling the motor.

 

i was told that the headlight harness and everything all tie into one main harness which goes to the fuse box and is tied into the engine harness as well. Is this true? I dont want to butcher and patch hanesses together so i want to make sure i get the whole thing.

 

what kind of time frame would i be looking at to remove from the donor car?

 

Also, what are the differences between the 3.1 MPFI and the 3100 (OBD1) Harness? I know the EGR is different, but what else?

 

i was thinking if the 3100 harness would work, i could get a slightly newer one and hopefully avoid the same problems that i am having.

 

Also, how ard is it to replace the Ignition system (ignition box and coil packs).

 

i am expecting a FULL hard day for all of this but anyone that has done anything like this before, and may have some useful hinds, i would GREATLY appreciate the help.

 

 

 

 

On a side not about the spark plugs, i will post pics as soon as i find out where the hell my little cable went for the digi cam. The gap on them as almost 1/4 inch!!! im surprised my car was still running, and the spark plug wires litterally crumbled apart when i was taking them out.

 

- Justin

[LukeZ34]

Have you checked all of your grounds? What happens when you loose power, does the motor just die, or does everything in the car die (lights, radio etc.)?

[92turboLE]

check all grounds i could trace/find.

 

EVERYTHING in the car dies, EXCEPT my gaugelights and sometimes my headlights.

 

Im talking, all interior lightling, radio, motor, blinkers, hazard lights, EVERYTHING dies. Whats really odd about it is that the gauge lights stay on, and like i said, sometimes the headlights and tail lights, thats it...

 

When i take the key out after it dies, even the chimer for the headlights is dead until the car powers up.

 

I have also checked all my major power wires, from the battery to the fuse blocks, from alt. to batt. everything.

 

i dont know what it is. I suspect something in the wiring harness because of the codes that it flashed, but what i fear is that the code 42 for the ignition could be because of the power cutting and not being able to power the ignition but maybe the ecm. I dont know.

 

im going to try the harness, but i dont want to get in over my head and find out that i cant get it back together before work on wed or something.

 

anyone that has done this kinda thing, PLEASE HELP.

 

the car is to the point where it is EXTREMELY UNSAFE to drive ans it likes to die on the freeway (and we have a lot of construction and NO WHERE to pull off and get out of traffic) and i fear that it might die on me when making a left through traffic or something.

 

- Justin

[Guest Anonymous]

Did you check the ECM grounds? They are on the back of the block at the bottom on the passenger side. There will be 2 seperate ones in the same area.

[Pontiac6KSTEAWD]

I think its the fusible links right at the starter or the hot point on the drivers side tower. Its making a irattic connection. Quite a common prob with all GM's of the 80 and early 90's. Check you links, I bet you find the problem.

[92turboLE]

I think its the fusible links right at the starter

 

Bingo!!! Kinda. After ripping out the ignition module and coils, i was poking around and noticed that on the main wire (that connects right to the battery basicly) where the wire had been crimped into the connector, One strand was loose and would barely ground itself out under rough conditions or sometimes just on its own.

 

Actually, the only way i found that is cuz i had to loosen the links to move the wires to get the middle lower bolt out from the coil pack.

 

so i removed the wires, cut and re-crimped new connectors on it and then heatshrinked them. Car is back in tip-top shape (well, mechanicly now anyways).

 

I put in a new ignition module and coilpack anyway since i had it out, and used plenty of die-electric grease. I also greased up the plug wire connections and a few other things.

 

started pulling a harness yseterday and got about 20 minutes into it and said fuck that. It certainly isnt as easy at one would think. not really doable with the motor in the car. so i didnt bother with that, although i really should cuz my wiring is fucked anyway.

 

i also now have to9 replace some of my + battery cables and wires do to my brother dropping a wrench on my starter and shorting the circuit and promptly igniting my engine bay. No serious damage as i just violently ripped out the battery ground, lol

 

all is good now, a few extension cords later and i have a temp fix for my power wires. lol

 

thanks for the input though

 

- Justin

[Slade901]

Good to hear that it is fixed now

[Go4DaMo]

My mom's 1992 Lumina 3.1 was exhibiting engine failure upon turning the headlights on yesterday evening. Today, I could not prompt it to fail upon turning the headlights on. Nearly one year ago, I recall this vehicle having an issue where the engine would start and idle, but as soon as I tapped the brakes, the engine would die. I believe it was a toasted battery, which I replaced. Is something eating the battery to where it's failing again?

This morning, I started the vehicle, kicked the headlights on, and began hitting the brake rapidly, trying to bring the demons out in the car, so I could fix it tonight, as its my mom's only transportation to work and I leave long before she does to get to my place of employment. All the vehicle did was sputter a bit, staying just above 1000 RPMs, before idling healthily below 1000. What gives?

 

My only thought (as I tossed and turned last night in my bed) is that there is a bad tach ground that's causing my remote start to continue turning the engine over even after it's running. This only happens occasionally, but the awful grinding of the starter has kept me from ever using the electric start. Could this be causing my current problem?

 

Any input it madly appreciated. Thanks, everyone!

[AL]

Its possible Sam

[Go4DaMo]

I'm wholly unfamiliar with grounds. Where can I find this?

[AL]

I would look more at looking under the dash and finding the remote start system and uninstalling it

[Go4DaMo]

Really? Mannn...I've had to uninstall every stinkin mod to this car, but the remote start. What if I asked Mark where the tach ground's at and see if that's the issue?

[AL]

Good idea