hi guys, need your help...bought my 96 XJR about 3 mos ago(japan spec)...worked on the suspension, interior and some paintwork.now im on to the engine...accelerates very poorly and consumes about 3 kilometer per liter of fuel!! replaced spark plugs,fuel filter, air filter and engine oil. engine idles very well with no fault codes..worked on the exhaust system also(no leaks) removed ALL cats..removed slack from accelerator and throttle cable.Using handheld OBD2 scanner, i only get 37% throttle position on wide open throttle. idles on 12.9% at 700rpm.
do i need to replace my TPS or have it calibrated to get those horses out of the engine? any suggestions?

 

I seriusly doubt the calibration could be off that much. I think you need to"come up with" a TPS!

 

I agree with Ross.
But if you replace the TPS you might need to use a WDS (or PDU) to perform an ENGINE setup.

With a full setup.......
You could test/set the full throttle 'kick-down'.
TPS adaptation.
Oxygen Sensor Orientation.

bob gauff

 

thanks for the quick reply Ross, what do you mean by"come up with" a TPS?

 

thanks bob,a jaguar dealer here in manila charges too much for a TPS adaptation...i will try to a find another shop who can do it..do i need also a oxgen sensor orientaion after replacing or calibrating the TPS?

 

The Oxygen sensor orientation is only needed if the ECM or the PROMS in the ECM have been replaced.

I just do the entire setup with my WDS when I have a car in for throttle or ECM faults.

bob gauff

 

thanks bob for the info. do you think i need to replace or at least have my TPS calibrated? im hoping this would solve my poor acceleration issue

 

Check the Rochester valve under the back seat that's what it sounds like to me

 

Have you already adjusted the accelerator cable? easy fix takes five min. you have two adjustments bc its an xjr.

 

yes jeremiahjaguar, ive adjusted the accelerator and throttle cables already and still 37% on WOT...any other suggestions? thanks

 

the kickdown switch is under the gas peddle, disconnect the wire to the switch and take it down, turn clockwise, as far as it will go. this should give you a little more throttle. But if this does not work it is your tps gone bad.