The car wouldn't start recently--wasn't the battery or fuses, so I called AAA over and the guy managed to get it started by whacking the starter while I held the ignition. He told me the starter was probably shot, and I should drive it to the mechanic as he wouldn't guarantee it would start again once I shut the engine off. Well, today the mechanic told me it was the wiring harness (I know the wiring harness is pretty fried and needs to be replaced). I still don't really get the bit about the starter, though. I mean, if it's the harness, why would whacking the starter help? Anyone have an explanation for this? We're having cold weather at the moment if that helps.

Anyway, the mechanic of course is saying it's going to be $800 for the new harness. I just searched the archives here and think I'll probably buy a new harness from IPD or off eBay and try to do it myself.

Thanks for any info.

I just finished doing this on my 1987 (manufactured 8/86) project car (see my other post from tonight). In my case, I did not need to replace the entire harness, because only a few wires were actually bad (i.e. crumbling insulation), so I just inspected each one and replaced as necessary. But replacing the whole harness might actually be easier (but more expensive). Removing the intake manifold, idle air control motor, and alternator is a must for this job.

As for the starter not working, it could be because of the bad harness... there is a little red wire that connects to the starter solenoid and the other end of it is at the key. In my car, this wire was one of the worst. Maybe in your car it is shorted out, corroded, or broken.

Good luck!

Thanks for the reply. There seems to be some disagreement on whether or not you have to remove the intake manifold. I saw this post when I was going through the archives:

http://www.brickboard.com/RWD/index.htm?id=386492

I also have a '88 240 and was thinking I could use that as a guide if I get confused about which wires go where. Are there any good instructions printed somewhere for a wire harness replacement? (not the Simon Eng method)

I'm sure it's possible not to remove the intake manifold, but my hands are just too big and clumsy, and I had a new manifold gasket laying around, so I just went ahead and removed it. I feel that I would have spent more time fumbling around and would have way many more banged up knuckles otherwise.

As for keeping the wires straight... I labeled the fuel injector, MAF, IAC motor, and throttle position sensor connectors, because they all look the same. The other wires (the single wires going to sensors) I found to have different connectors (i.e. male vs. female) whenever it was possible to confuse two, EXCEPT for the dash temp sensor and knock sensor which I got confused and had to look at another car to figure it out. Most of the wires are also different colors so you could write down what color goes where to keep things straight.