Hi, my 2002 XJR has gone into limp mode twice now. But when it does, all I have to do is turn the car off, turn the key to the on position, let it sit, and start it again, and the limp goes away. When it does go into limp mode, it runs really rough. Almost like not all the cyllanders are going. It happened twice, pretty spaced apart time wise.
Not sure if this is a seperate or related problem, but sometimes I go out for a some fun sport driving, hard acceleration, high speeds, etc. When I turn off the car, and hours later turn it back on with the sport mode switched off, I'll leave my neighborhood slowely. When it shifts from first to second, first it revs higher than normal (as high as 4,000 rpm), then when it does finally shift, it's really rough into second. It jerks, but after that, all is well. This does not happen EVERY time I go out for a fun drive. Any ideas?

 

Boy, can't even begin an internet analysis on an intermittent problem like this w/o lots more information. Any CELs, codes, anything else you can offer? Lots of people are going to do lots of guessing with what you've offered.

 

I used to get "restricted performance" in my S-typeD, but so far, ever since I wired a huge capacitor combo*. across the battery (with a series fuse of course) the errorcode has not appeared. The symptoms were exactly as you describe.
The other fault re. gearbox, I assume the ATF fluid has been checked/changed for fresh good quality stuff? 'Cause the effect you describe would make me think of low fluid rightaway.
*The combo. was two 10,000microFarad electrolytics at 25volt working plus a 20microFarad plastic film capacitor all in parallel. I used a 3amp fuse in series -- I've had a car catch fire due to bad design in the electrical area (Citroen C4).
Leedsman.

 

I'm with Leedsman, think you might be having a transmission issue. If the lights are coming on, there might be a code. Did you check for codes?

 

well, no lights come on when my transmission shifts rough, but of course lights come on when it goes into limp. I have not had any codes checked, but I do work for a dealership that has the equipment to read them, so if it happens again I will check for codes. I'm sure the transmission does need new/cleaner fluid in it. I'll have that taken care of too.