1998 XJ8 - no kickdown
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#2
Welcome to the forum cbrit,
I've moved your question from Jaguar Forums Feedback & Suggestion Centre to X308 forum. This is the place to post technical questions about your model.
Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.
Graham
I've moved your question from Jaguar Forums Feedback & Suggestion Centre to X308 forum. This is the place to post technical questions about your model.
Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.
Graham
#3
#4
There are 2 main reasons that the kickdown is not working. First the throttle is seeing and communicating to the ECU that you are at Wide Open Throttle (WOT) and second is that your kickdown switch is defective. Since the ECU is seeing something for kickdown and can't match values to determine an action your switch is most likely good.
That leaves you are not at WOT, the common cause for that is stretch in the throttle cable. If you remove the snorkle intake and check the cable it probably has too much slack to go to WOT. You can clip the tie wrap that holds the cable to the throttle body and lift the square plastic holder out and adjust the cable to remove the slack. If memory serves me from the last time I did it you rotate it towards the throttle. Once the slack is out reinsert and apply a new tie wrap.
That leaves you are not at WOT, the common cause for that is stretch in the throttle cable. If you remove the snorkle intake and check the cable it probably has too much slack to go to WOT. You can clip the tie wrap that holds the cable to the throttle body and lift the square plastic holder out and adjust the cable to remove the slack. If memory serves me from the last time I did it you rotate it towards the throttle. Once the slack is out reinsert and apply a new tie wrap.
#6
The fuel filter is in front of the left rear wheel, but that is probably not the problem. As Vern suggested, the throttle is not opening all the way, an easy check. It's also possible that the kickdown switch needs adjusting. It's under the throttle pedal and can be turned to adjust. But check that the butterfly is opening all the way first.
The engine will rev freely in neutral, but should not go over about 3000 rpm by design.
The engine will rev freely in neutral, but should not go over about 3000 rpm by design.
#7
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#8
#9
I know my 98' XJR has a kick down switch under the gas pedal. I too wanted to know what I could do to improve my kick down drivability.
Btw, if you ever need to adjust that switch, you must pull up the carpet to gain access to the electrical connector, unplug it and turn the entire switch and short harness together or else you'll ruin the switch.
Btw, if you ever need to adjust that switch, you must pull up the carpet to gain access to the electrical connector, unplug it and turn the entire switch and short harness together or else you'll ruin the switch.
Last edited by Addicted2boost; 07-23-2018 at 05:01 AM.
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