Went out this morning to start the can which it did but then stopped, started it again it ran then stopped. No idea. I then started it and kept it running using my foot on the throttle peddle and took it for a short drive making sure I didn;t let the RPM's drop under 1000, once I got back home and in park I let my foot off the gas and the car went back to it's normal rpm of around 700. So does anyone have any idea why this might happen and they return to normal on it's own.

Thanks

 

Many possibilities.

Do you have a scan tool to check for trouble codes? Sometimes the codes are your only clue with these come-n-go problems.

My own XJR was giving very similar symptoms a couple months ago and I identified a couple of bad coils. Replacing them fixed the problem. In the last couple weeks I've be feeling the beginnings of the same thing. I'll check the other four but I'm ready to just replace them and be done with it.

If you have an ohm meter you can check your coils yourself. The primary resistance resistance (measured across the two connector pins) should be .75 ohm. Ideally you'll check them ASAP after the car misbehaves.


Cheers
DD

 

Hi Doug I do indeed own a code reader and the car is showing none, I pulled all the coils this morning and they all seem to be between .8 to .9 ohms you stated they should be 0.75 so are these starting to go. Now I had been out with the car so it was hot when I checked them would that caurse them to be a tad high.

If I need new ones where would you being looking. I live in Canada but only 10 minutes away from Down town Buffalo so have access to most auto parts stores in the USA...

Thanks

 

Where to get coils? Tough question. The OEM coils are expensive....about $160-$180 each, I think. Aftermarket replacements get mixed reviews with respect to longevity, if labeled "Made in China", but range from about $50-$130 each.

I took a chance on Beck Arnley untis for $60.00 each from Rock Auto. Crossing my fingers as to how long they last. The coils themselves have no markings of any kind....but hopefully ...*hopefully*...Beck Arnely wouldn't sell outright junk as they have a good reputation to protect.

You might see what your local auto parts store offers or call Covnetry West, Motorcars Ltd., etc.

Cheers
DD