Hey guys I just picked up a 1987 Jaguar XJ12 from an auction and I cant get the V12 engine to start. The auction house confirmed that it started and idled when it arrived. It was towed home and after a long charge of battery it started and died after a few minutes and has not started since then. I put some gas in both fuel tanks and put a fully charged battery from a 2001 Kia Sportage in it and still wouldn't start. The cranking is pretty slow which is why I thought the battery was not giving enough charge. I noticed smoke coming out of the positive terminal when I hooked up the new battery. Any suggestions to this problem will be helpful. Thanks.

 

Start with the obvious;
Do you have fuel at the fuel rail (injected or float bowls if carbs)
Spark at the plugs (both sides of the V)
Clean air filters
Check these and report back.


Small battery with loose terminals perhaps?

 

I have bought some starting fluid. I will try it and update tomorrow morning as its cold and very dark outside (im in Canada). I do believe the battery is not providing enough charge as cranking is pretty slow.

 

First things first. Get a strong battery so the engine will crank properly. Plus, the fuel injection system won't work right if the voltage drops too low.

After that, check for spark as suggested.

Cheers
DD

 

UPDATE: I inspected the battery terminals and found that the positive terminal was in very bad condition and full of corrosion. I replaced the whole terminal and its wire with a new one. I also put a battery from 1995 Lexus LS400 and it fired up. After letting it idle for a few minutes I engaged the gear into drive and it started moving on its own but as soon as I pressed on gas pedal, it died. I put it into reverse it moved back on its own but as soon as I pressed gas pedal it died again. But the good thing is that it starts on it own now. Thanks for the earlier replies as they definitely helped me. Here is a picture of the old terminal.

 

The 1987 XJ12 is from the Series 3 range as the Series X300 is from 1994.4 to 1997 . Might find more V12 5.3 liter HE ( high efficiency ) with the Lucas CEI ignition system engine regulation information in that post area . Might find also in the XJS ( X27 ) area as it had the same engine for that year range . Might be as simple as replacing the old fuel in the tank . Grant Francis made this write up on the V12 5.3 HE no start condition :

https://www.jaguarforums.com/forum/x...he-v12-178286/

and see also :

http://www.mediafire.com/file/722956...erformance.pdf

And see also wiring guide :

http://www.mediafire.com/file/n8w2qu...er+111+XJ6.pdf

 

See page 160 :

http://www.jag-lovers.org/xj-s/book/XJS_help.pdf