89 XJS, Stopped while driving

XJ-S
22

I read somewhere that if the Ignition Module is either working or not working, does that mean permanently or only while its not working because of heating?
If the car works most of the time, could the module be bad also?

Thank you

23

It can definitely be intermittent based on heat. I once forgot to put heat paste on a module, ran fine for 15 minutes when cold. When warm and engine died, I had to wait 5 minutes to start again, and it would only work 1 minute before it died again. Repeat.

24

This cable can cause intermittent problems when insulation is cracked from long exposure to heat. This gave me many weeks of grief. Car would run great, and then it wouldn’t.

25

which cable do you mean?

26

Kirt’s response above refers to a coax cable. These particular cables will get very brittle after being subjected to so much heat over the years. Interior conductor is separately insulated then wraped with a braided shield. After the insulation brakes down the conductor and shield can short out. If car starts and runs fine movement or expansion due to heat can cause the intermittent short, engine shut down and lotsa head scratchin. Good luck!

27

Thank you. Great info.

28

Hope it helps. It took me a while to find the problem.

29

Hello Greg

I tried to take out unscrew the ignition amp, the two screws on top were too tight, they would not move. I was worried they might break. Is there a way to remove them.

Thank you

30

Is that the wire attached to the Ignition Amp screw? The wire is exposed by the screw and another place, I covered it with electric tape.

31

You mean the two bolts holding ignition amp box to intake manifold? Should simply unscrew.

32

Yes, they are very tight, how much force can I use? I don’t want to break anything.

33

Question:

Yes, they are very tight, how much force can I use? I don’t want to break anything

Amateur inquiry: you try a little WD-40 on those? Might help.

34

you shouldn’t break anything, those are simple threads/bolts. Probably just a bit of corrosion. Just squirt some WD40 or PBblaster down bolt, let sit a few minutes, and then force them loose. They are not meant to have any torque on them at all.