I posted a couple of days ago and from some good input I was able to start my 1990 740 GLE - car has about 120,000 miles on it - 5spd, and drive it home.

Anyway I found from a posting that a tap on the side of the centre console and 'voila' the car would start. I thought that this would be a piece of cake. I read through the FAQ's and found out how to get at the fuse panel expecting to find a melted fuse socket or a bad wire. When I opened it up all looked like new.

I was able to pull out the ceu and visually inspect the panel- top and bottom, pulled each relay one by one to see if there was any visible corrosion, - there was no problem that I could see. Nothing.

Then, with the panel out I tried to start the car and it would not start, it just kept turning over. I moved the panel with a little twist and it started.

Put the ceu back in and tried the car again and it would not start, again I shifted the ceu and it started. I do not know if it is a wiring or relay problem? If it is wiring I do not know where to start, there must be 30-40 wires tied together feeding into the back of the ecu, if it may be a relay is there any way to check? Opening the wiring harness scares the hell out of me.

Has anyone dealt with this problem, or is there is recommended course of action that anyone could recommend before I am in over my head.

Thanks in advance






Then I

Thanks, I will try these tonight and post results.

Final note
I found the problem - this is note for anyone else who may have this problem.
I did take out the 'fuse box' and looked at the fuses themselves but not carefully enough, I took out the fuel pump relay, carefully opened it up and thought I saw two questionable relay solder joints and re soldered them. Put the relay back in position, tried the car -it stsrted, feeling I had solved the problem I put the fuse panel back in place tried the car again and nothing. So I went and spent $ 60.00 on a new relay, installed it and still nothing. Came back and checked the brickboard again and started at the beginning again. The fuses- a closer look showed a very slight brown stain on the number one fuse. Venturing on I found that you can carefully pull the top of the fuse cover off and you have access to all of the fuses - copper connections and found that two of them had some heat discolouring and I cleaned them up, straightened them, they actually were a bit distorted. Put it back together - make sure that you which fuse goes where because once you take the cover off all the fuses are not held by anything and easily fall out of the cover. And then I started and re started the car with the fuse panel in a few different position always with success. So I re assembled and I think that that was it.
Hope this helps someone.
I am a rookie mechanic, so I am thankful when any body saves me from the real ones. That is the only way I can afford to drive these cars.
Cheers.

Commonly, the solder joints on the relay base fail, so it is worth re-soldering before spending money.
--
BillB

The relay I would suspect would be the fuel pump relay. It could be the relay, or it's base. The FAQs show how to jumper around the relay, if your intermittent starting goes away, its the relay. If not, you may have a bad crimp leading to the base that the relay plugs into.