Hi, I have fitted a new ECU to my X300 Jaguar xj6 1997. Engine started straight away, but at high revs, pressing the throttle did increase the revs, but it would only drop down to the same high revs when i took my foot off the throttle. I'm wondering if there is any electrical part to the ECU that would control the throttle or the idle speed. Thank you. Robert.

 

Yes! The X-300 ECU is "married" to the TPS and the connections of the lambda sensors. Look in the Jaguar documentation for the "TPS calibration" and the "O2 Orientation" procedures. Unfortunately, both take dealer level software like WDS or IDS.

 

Hi, Thank you for your reply. Might the adjustments to these sensors be a task i could attempt myself, as the nearest Jaguar dealer is miles away. Regards, Robert.

 

Well, you can do it yourself if you have WDS or IDS software, which is what the dealer used.

 

Might be a shot in the dark, but could a hard reset on the ECU sort out the engine racing when i start it up. Iv tried pressing the throttle etc but it just revs faster. Unfortunately i live in a very remote part of Wales so there's not much chance of finding a Jaguar dealer or the right test equipment round here. Regards, Robert.

 

It will certainly not hurt anything. I think your radio needs a code, so know that before you do it!