Hi I just baught a 1986 XJS with the 5.3 V12. I baught it about 2 months ago and for the past month I've been trying to start it. The battery looks fairly new so I decided to to charge it, it helped a little but I still had to put the jumper cables on it from my ford pickup. I then connected my tow truck also and it had cranked a little but wouldn't start.

I continued trying for a few days and it actually started, but it was smoking a little and the oil light was on so I decided to shut it off, also some gas was collecting on the drivers side air filter. The oil was the same as it was before I started it, perfect and gold. I think that the oil pressure gage is broken because it was reading zero but it was still running ok, that might be why the oil light turned on.

I continued trying to start it for weeks, I then tried starting it one day with starter fluid and then it almost turned over, but thena fire started in the Drivers side air filter,but I was able to put it out.

Later that day I tried it again, without the starter fluid, and it actually started after a long time of cranking. This time it was running pretty good, staying steady, and then I tried pressing the gas pedal a little and it didnt stop. I then watched all the gauges and they seemed fine, except for the oil pressure which was still reading zero and the light was still on. The temperature guage was reading half way, then rose a little bit, but then I decided to shut it off because I never checked the coolant level, so I decided to stop for the day and shut it off.

The next day I tried, but it just wouldnt start, just cranking about to start. I tried again yesterday and the gas guage was almost reading empty, when I first tried it was reading half, after a while it was reading a quarter, now almost empty. I dont understand where a half tank of gas could have gone. Also, I can smell gas while trying to start it, and gas doesnt collect in the Air filter any more.

I've been thinking about putting a chevy 350 in but I'm not sure if I should keep trying to get this V12 running.

 

Hi again, about the oil light, while I had the car running, both times, the oil light was on only while it was idleing, when I started to race it up a little the light would turn off.