1996 xj6 vdp

When I hook up a scanner the TPS only goes up to 50%. Is this normal? I know some other reading don't always show they way they should on these cars.

 

Does it go to zero at closed throttle? There are slack adjusters in the cables, one from the pedal to the traction control module, and another from the TC module to the engine. Adjust those and see what happens, making sure that it goes back to zero at closed throttle.

When I got my XJR the cables were way out of adjustment. I could accelerate much faster after adjusting so I could get full throttle opening!

 

Any instruction on how to adjust the slack? if there is any?

 

I just turned the adjuster to shorten the cable until I was able to get close to full throttle when I put the pedal to the floor. I think the best I could get was 97% and still have it go to 0% when I took my foot off. You don't want to the cable too short or it will hold the throttle open at idle.

I can't recall how the adjuster works, but it was fairly obvious. It's the plastic piece mid point on the cable.

 

I borrowed my friends VCM today and tried doing a calibration of the TPS and the Pedal Position but it still only goes about half way. I took off the intake elbow and with the pedal to the metal the throttle body only opens up about 1/4 an inch or about 1/3 of the way. I have no slack between the traction control module and TB and it seems like the line between the traction control module and gas pedal is tight too. Does the TC module do any kind of step up ratio?

 

I THINK.... I recall a TSB about the cruise/traction control that addresses adjusting the throttle cables.... check out the TSB sticky section.

There definitely are some instructions in a thread here related to adjusting the cables though as I adjusted mine a year ago and misadjusted throttle cables is a common issue/fix for high idle. In fact, I'd recommend searching for "high idle" and I bet you find some threads and info on adjusting the cable.

.

 

I took te cover off the TC unit to expose how the cables work inside and What I noticed is that the pedal moves one pulley while that one pulley is connected to another one with a clockspring type mechanism that steps up the ratio going to tge throttle blade cable. What I noticed is that it seemed like the resistance from th throttle body was higher that ne spring in th TC uńit. I took out the little spring that goes from the throttle body lever to a bracket and now it opens it up all the way.

I used the VCM to clibrate pedal position and kickdown and the car runs like a champ now.