Dear Jag Lovers,

I have recently been very active on this site because my new project (4 Months in the working) is a 1983 XJ-S V12 Beautiful Beautiful car. I was cleaning my instrument panel (took it out the official way) nothing strange. After putting it back and reconnecting the battery I started the engine. Now the strange thing happened the back lights started to switch on and off and when I switch my lights on the car won't switch of any more (engine keeps on running). very very strange. would there be anyone that could advise me on this ghost in the electrics.

The other question is if anybody has any experience or knows a good addres with cleaning this massif V12. I have a lot of diff cars but never had such a dirty engine before plus the electrics makes it look a bit tricky.

Many thanks on forehand,

 

My first thought would be that something was not plugged back into the same place when you put it back together. It could be something as simple as a groundwire.
I also have an 83 XJ-S, but mine is a convertible! Can't wait to get it on the road!

 

For cleaning engine and engine bay use S100 cycle cleaner. Works miracles, and hoses off with water. Must go on cold. S100 is made in Germany, but sold through Harley Davidson dealers in the US. Better than anything I have ever used.

 

Thank you for the electric answer but that should not be the problem i have checked that double. Its for on my engine V bit where the erco pump is its a lot lot of gunk (oil).
mine is at the garage to I shattered the Diff during track day. Btw I live in the UK so il get it here.

many thanks

 

My first thought on the electrical issue is a bad ground/earth. Letting my imagination run a bit wild, perhaps a poor cluster ground causing a backfeed from the tachometer to the ignition amp?

I don't know if that's even possible...I'm just musing. Ground/earth issue can cause very strange symptoms, though. On my old XJS the tachometer would stop when the lights were switched on. I added a redundant cluster ground.

Don't use high pressure water when cleaning the engine. You'll almost surely regret it.

Cheers
DD