The check engine light stays on on one of my 95 XJS. I was told by Jag that the most likely culprit was the petrol cap and I sprayed it with WD-40 and lo and behold, the light went out and stayed out. Recently, I had it serviced, oil change and air filtre. Now the light is back on and no ammount of fiddling with the petrol cap works. Any suggestions short of paying an arm and a leg to have Jag put it on the computer?

Submitted by newvegasbear@y… on Mon, 06/14/2010 - 19:57

HI:
I tried both auto zone and Pep Boys and neither had a code tester for Jags. I tried unhooking the battery for a couple of hours and it did not go out. At that point I went to Jag and paid $99 to have them put their meter on it and it turned out to be an air pump which they gladly changed for another $325. Anyway, the light finally went out.

Jim

Thanks for the suggestions though!

Submitted by SE98-32482CJ on Fri, 06/04/2010 - 15:20

James Doug is right but if it is a minor code try disconnecting the battery for an hour or so. The code may still be stored but the light will go out. CE lights are often set by temporary fuel or oxy. sensors--there is still not problem but the code sets.

Submitted by dougdwyer1@com… on Fri, 06/04/2010 - 15:12

With the check engine light on there should be trouble codes stored in the on board computer. For $40-$50 you can buy your own "code reader" to access the codes and then you'll have at least a preliminary idea of where to start looking for the problem.

Without knowing trouble code it's pure guesswork as to what might be wrong. There are dozens of faults that will trigger the check engine light.

Some of the chain-type auto parts sotres will read trouble codes for free.

Cheers
DD