Hi guys,

1999 XKR 4 litre SC convertible.

Would be grateful for any help please. The car is still under warranty and the dealer has been very good thus far, but our old girl has developed an issue, albeit a small one. She doesn't want to start from cold, she cranks for about 30 seconds, the green check engine light comes on and then with holding the accelerator down, she'll start. Once she's warm, no problem at all, it just seems to be from a cold engine, then there's also a little white smoke on starting from the exhaust.

Chain and tensioners have all been done, new battery, spark plugs, one failed coil pack recently changed, compression test done prior to purchase which was good. She goes like absolute stink when running, no misfires or issues, it's just this starting malarkey.

Please help an old girl help her old girl out with some clues!

Thank you.

 

Data is what you need. The alternative is to throw parts/money at the problem and see what happens. You need to figure out what the car is trying to tell you with that check-engine light. Cheapest is to buy a wireless ELM327 device and pair it up with an app on a mobile device. This will give you the list of standard OBDII codes the car is diagnosing for you. Then you can look these codes up in our (excellent) documentation and go from there. Be sure to look up codes based on the exact year as, unfortunately, some codes have been re-defined over time.

GUESS: It sounds like the primary fuel pump is dead, and the car switches to the secondary pump after a few unsuccessful starts (this is by design in the older XKR). This is pretty common on our aging cars, especially if the car has not been driven a lot.

Best of luck, keep us posted.

 

Thanks so much for the reply Mertz! She's still under warranty so the dealer will have to sort it but that's great to have some ideas of where to look. The dealer has the JLR fault diagnoser, so we'll see what happens.

I'll let you know!

 

Your dealer should know this, but it won’t hurt to mention the primary fuel pump suspicion.


on the 4.0 L XKR’s, if the primary fuel pump is out of action there won’t be a code thrown as long as the secondary fuel pump comes on line immediately, ie within a few seconds. Which gives you the slow-to-start scenario.


the test involves pulling the relay for the secondary pump and seeing if the engine still starts. Dealer should have the relay map as part of the fuse / relay diagram. Here is mine for my ‘02 XKR, which I believe is the same as your car’s.

Z

 

Thank you so much for the reply Z, that's a great diagram, I'll definitely mention the primary fuel pump as being the main suspect, thankfully, the dealer has become a friend from the Jags we've had from him over the years and he's open to suggestions to pass on to their mechanic.

Much appreciated, thanks again!