hi,i have a 96 4.0 sovereign straight 6 and it has been sitting for 2 years,i attempted to start it yesterday and the revs went upto around 4000rpm and stayed there,what should i be looking for to cure this,any help very much appreciated! dan

 

Welcome to the forum, Dan.
Please drop by the new member's section and introduce yourself so a mod can take notice and upgrade you to full status when you've completed all the prerequisites.


Meanwhile, I reckon we should all pause and give thanks that yours lit after 2 years! https://www.jaguarforums.com/forum/x...ngines-120221/
Normally, sticky throttle plate is at idle and folks break the cable or mechanism trying to get above idle. Just a guess but maybe you have a gunked-up throttle body and it is stuck partially open?


I'd recommend pulling the throttle body and cleaning it thoroughly, taking care not to ruin your TPS in the process. Search throttle body for some how-to threads or maybe it is in the stickies. Also, drain & replace that aged fuel before running it again or you'll likely face a significant fuel system cleanup, possibly including injectors. Also time for a complete fluid renewal project: fuel, oil, coolant. But as to fast-idle, I'd look at the throttle body, then maybe the spring (normally will come down after a kick or two if it's the spring problem.) Maybe IACV or TPS calibration. Others will chime in with better ideas...


Maybe something useful: https://www.jaguarforums.com/forum/x...e-down-113680/

 

I will vote TPS calibration. I'd even go so far as to put a ten dollar bill on that...