I had an issue with my ‘04 XJR this morning. It cranked over slowly and sputtered a bit but didn’t start. Did that a few times then added a jump pack. It turned over a bit faster and eventually ran, but it ran horribly. Really rough idle and knocking and a restricted performance message along with a flashing check engine light. I took a different car to work. I did step of the gas pedal a few times while cranking it, so have I just flooded it or has something more serious occurred? It was slow to start yesterday but ran fine. The weather had been cold recently.

 

do you have a OBD code reader? You need codes to help troubleshoot and get help from this forum.

 

I don't have an OBD reader. I tried again when I got home and was in less of a hurry. It still ran roughly at first, but did improve with time. I think there may be a coil going out, or having trouble in the cold. As soon as there was any heat in the engine it smoothed right out. I took it for a 18/20 mile drive and it seemed perfectly normal. Something like this happened last winter, but it only ran roughly for a few seconds.

 

Sounds like it could be some bad fuel

 

Pick up a Foxwell NT510 code reader.

 

+1 on the NT510

 

Hey Gere,
When you get your NT510, check cold start fuel pressure (in PCM Live Data). If its low, replace the fuel filter and recheck. You may have failing fuel pump...

 

That seems like quite the tool. I'll look into getting one. Can it do suspension programming?

 

Preloaded with the Jaguar program is the way to go.

Had a hell of a time downloading the Jaguar program,

Find new things almost every time i play around with it.

Really pretty impressive, just how much, is programmed into these readers

 

Slow turnover is a rundown/bad battery, bad ground/earth to body and/or engine etc. If the voltage gets below a minimum voltage some adaptations are lost and have to be relearned. Causes a very rough running engine next start. Will cure itself after driving a while. Bad engine ground strap is said to burnout the brake flex hoses as a side effect!

 

did you get your car sorted ? sounds like a bad battery . lots of problems from a low / week battery .

 

Its been fine since but I haven't dived deeper into any potential causes. The day before we had had a snow storm, so I started the car, moved it to shovel underneath, then put it back. It didn't run for very long and the next night got very cold. So I think it was a slightly weak battery in bad conditions. The battery is two years old I think. I'm not going to make any further attempts fo fix the car either, it has so many issues that I've decided to replace it. Looking at an XE tomorrow.

 

I'd go with a battery problem, if it lay for a while the battery will have discharged, then trying to crank it will drag more power away from the other systems and it WILL chuck up more codes than you can shake a stick at, some of these codes will go away once the system gets proper voltage, but others will stay, until reset with a code reader, and could cause more issues, also if the battery is weak, then the system will not have enough voltage to keep everything running at peak performance, even if you drive the car a 100's of miles. Get the battery tested, As most on here know these cars do not like low voltages.

I had to jump start mine a couple of times lately due to lack of use and I got all sorts of problems, until i recharged the battery