Landseer

That's worse than usual. Do you also have scorched blue/blk wire on distribution plug coming out of panel? Didn't realize you had toast on back too. Is that the one you were giving tracing coordinates for?


I've had a big grey wire melt back there in a subtle way. It melted only where it touched other wires. It actually connected wire to wire with one of its neighbors, but didn't scorch so you couldn't seen evidence of melt. The perpetrator was related.to defrost. Rooting around was how we discovered it.

Chucks928

Land, yes . When I pulled the CE panel for a clean and refresh, that scorched wire on the back was the very first thing I saw. It connected fuse #4 to, what I figured out, was the J5 connection on the wiring loom connections. When I finally got into the car to assess the wiring down there, I found the Blue/Black wire at the J5 position also completely melted as far as I could see. I cut into the main loom covering yesterday as far as I could to see how far it had melted. It appears melted as far as I traced,but havent found exactly where its final destination is. It hasnt melted into any other wires as far as I have seen, just melted onto others but not enough to get to the wires themselves. I,m wondering if maybe the PO had installed a far larger fuse in the panel at one time and when an issue popped up, it didnt pop the fuse but heated the wire enough to melt it. When I pulled the CE panel, the 8 amp fuse that was in there was blown. It may have been put in there after the problem and it blew right away and he never bothered to follow up. I would assume the fuse would normally prevent this from happening.

Landseer

I've never had more scorched wires then on 928/44/51 cars. You are probably right about the fuse thing. Allan, our master electrical guru would be able to frame it up compared to other cars. Just seems low on robustness.

A lot of mine have had scorched brown ground wires too, esp inside that console. In tracing a burn what I've found is here and there the burn is bad enough to short with another wire, like, some random place a foot into the bundle, center of bundle...
P
Did I catch a clipped ground wire in one of your CE pictures?

Chucks928

Land.....I clipped that wire to pull that panel, After it was pulled was when I realised I could have just disconnected it from the ground point. Its been resoldered.

Chucks928

Aanddd.. we have a winner! The toasted wire is for the ashtray light! I can replace the wire and install a new bulb, but is there a common issue that would cause it to burn out? The PO was in there installing an aftermarket radio, and it does work but not sure if that was the main issue. The grounds for both the light, the lighter and the clock are disconnected.....any reason to not reconnect?

Billu

There should be a white/silver pad that sits on the drive tunnel under the ashtray, appears to be there to prevent this wire(and the lighter) from grounding out.
Usually a melt like that would be caused by the terminal shorting to ground, not shorted going through the bulb.
I would certainly re-hook all the grounds.
Also, in my experience, the bulb holder isn’t secured real well to the ashtray, so it might have just been pulled loose by the PO and bounced around til it shorted.
Always an adventure trying to figure out what was done by past owners.

Landseer

Same thoughts here
That brown / white needs a little repair too

Chucks928

Good catch on that brown wire....1 more to fix. It looks like a PO may have just cut the original radio loom . Instead of tracing all the wires they just spliced in where they could to get the radio working. A red wire going to the clock was cut, then a fuse holder spiced in and run to the new radio. For now, im going to fix that brown and leave all wires for the ashtray and clock disconnected and covered up. After cleaning the CE panel and repairing wires I now have all my tail lights and sidemarkers working and all my interior lights except those in the console. Time to start work on the engine looms.

Chucks928

Just a comment on how frustrating this car is! No matter what I do,fix,or replace on this car.....consistency still eludes me. As an example... this car has always had a cold start issue,thats where the chasing started. But its never been consistent. One day it will start like a new car,next day I,m fighting it to get it to start and run decent. Over the winter it was in storage,but on a 40 degree day I went out,hooked up the battery and it fired before i had hardly touched the key,and sat there and purred like a 928 should. It did that 3 times over the winter. This spring as temps hit the 50s, off came the cover,hooked up the battery and its a fight all over again to get it to fire and keep it running! My refresh of the CE panel has helped fix a lot of the lighting issues I had but not the starting. Even last summer,with the cold start issue,once temps hit 60 or warmer it was fairly easy to start when it had a mind to start ,now..... back to pulling my hair out ! UUUghhhhhh..... The damn thing is laughing at me behind my back..

drscottsmith

As I have wrenched on mine for over 4 years now, I have learned that every electrical connection in the car is suspect, and, in many, many cases, they are the reason for a lot of issues. In your latest case, removing and using deoxit on the electrical connector at the Cold Start valve may solve the issue. It could also be one of the grounds on the engine has a bit of corrosion on it and in the right ambient temp, that connector shifts ever so slightly so the corrosion impedes the floe of current. All of the fuel injection components ground to a screw on the passenger side of the cylinder head. Check your ground strap on the bottom (passenger side) of the engine as well and clean it good.

4 years ago I would have doubted anyone who posted something like this, but the more I have the car apart for fixes, the more I have learned to believe it. One of my buddies is having headlight issues right now and we think it is a problem in the ignition switch - of all places.

Nonetheless, you are in the absolute best place for help on these cars!

-scott

Billu

First guess on your issue would be sticky AAV. Sticks wide open unless it gets really cold, then pops closed?
I assume you have cleaned it.
I attached this to the old post you resurrected, but will also attach it here.
Check all the resistances of the inputs at the Ljet controller first. I chased a hot start issue for a few months until I finally found that the PO had soldered a potentiometer into the temp sensor wiring, hidden in a mass of wires above the controller. I was about to run a new wire when I found it.
See pg 18

Chucks928

Billu...I do recall that attachment. Thanks, It may have been overlooked as I was getting some great tips from fellow members and forgot about it. I'm being stubborn when it comes to this 928 and wont quit until its running and driving, but I've never ran into a car that has had so many issues and just when you think its finally almost ready to drive, it throws another issue , or the same issue back at you!

Chucks928

Thanks for everyones help with this wiring issue! While my CE refresh has revived all of the lighting issues this car has, I now have lost my power windows which is no surprise since the wiring in this console is so wanked up that any poking around was sure mess up something else. I,ll have to get in there and see what happened and maybe I can get my clock working also. I,m now tearing into the engine compartment wiring apart and will be pulling my AAV to service that. The car is back and running,but cold start is still an issue as is the rough running,which I,m sure is a couple bad injectors. Its definitely been a learning experience for sure! Chuck

sendarius

If it makes you feel any better about 928 electrics:

Shortly after I bought my '88, I went through the CE panel - correct value new fuses, liberal application of Deoxit, you know the drill.
I found six blown fuses, and a couple that were mis-rated.

Trouble is, I can't find six things that were restored to life by replacing those blown fuses.

Chucks928

makes you wonder!