I also am having a history of the check engine light. The diagnosis is always the knock sensor. This has been replaced often, since it was new. I bought the car in 2001 but the history from 97 has been the check engine light, resulting from the knock sensor. Has any one else had this problem?

Submitted by ji_190@yahoo.com on Thu, 10/13/2005 - 15:49

I saw your post and it reminded me of my experience w/ Bob Dunn Jag. I had a history from the first 5000 mile of a high idle w/ my 96' XJS. The previous service manager was great about doing everything and anything to make things right. Since he left, his replacement has more than disappointed me with treatment and service of my car. I have taken my jag to, Import Accent or EuroAccent(can't remember,old age?), its on Market St. in Greensboro. Check the phonbook. I have found them to be very good. If it is a problem with a history from the time of warranty coverage it should still be covered. I would write personally to the Head of Customer Service for Jaguar to complain and demand that they cover or reimburse you for the problem.

Good Luck,

Jud Werbela
1996 XJS

Submitted by mktr@charter.net on Mon, 09/12/2005 - 23:53

hi,the knock sensor senses vibration/knock,any tapping or other vibrationsin the engine may be picked up by the knock sensor and may set the ck engine lite. also the ecm checks the circut resistance and if its off for any reason it may turn on the lite. the function of the sensor can be checked with a lab scope. 1962 fhc 1970 fhc

Submitted by bonnettoboot@e… on Mon, 09/12/2005 - 20:30

I.m not sure how he would check the chain tensiner but if it were a timing signal problem seeting the engine to far advanced then the problem would be a sheared key at the crankshaft damper. if the damper moves so does the magnetic pick up thereby preventing the ECU from setting the timing properly, but first have someone check the ignition control unit vacuum connection in the right front side panel Jaguar affectionado and etc.

Submitted by dlrussjr@alltel.net on Mon, 09/12/2005 - 05:16

Bob Dunn Jaguar has done it in Greensboro. I have the history from when the car was brand new and it has always been the knock sensor. I live in Winston Salem, NC and have had other mechanics diagnose it and it is always the knock sensor, which has been constantly replaced. I use 93 grade at all times. Once the mechanic at Bob Dunn suggested to check the timing chain which started at a 1,000 dollars to even check to see if this was the problem.

Submitted by bonnettoboot@e… on Sun, 09/11/2005 - 23:04

Who has been doing the diagnosis for you amd how? And what grade of fuel are you using? Jaguar affectionado and etc.