My 2005 XKR just cuts out when it goes over uneven ground and coasts to a stop. When I try and start it all the check lights come on but the engine wont turn over. About 30 mins later the car starts normally on reduced performance, when I switch of and back on the car runs perfectly though the Amber engine light remains on. I have the fault cleared and then weeks later exactly the same occurs? Any help appreciated.

 

What codes?

Also, may be bad power/ground (or even battery plates).

 

System checks flagged up on the dash were:
Cruise not available
Restricted performance
DCS system fault
Low Brake Fluid
Gearbox fault
Not sure what faults were held in the computer as its in the garage but last time it flagged a sensor on one of the fuel pumps?

 

These strange codes are often indicated when the throttle position sensor is failing. Try cleaning the contacts in the plug, if this doesn't work you may need a throttle body rebuild or try to find the part. The last I heard, the part was not available separately although a number of people were trying to get the part made available.

 

Just a little info I have gleaned over the years on this subject....the TPS is a dual carbon track type that basically is a fail safe device, so it is not a standard one that you can get from another vehicle. It reports the results of both tracks to the ECU and the ECU determines if the sensor is correct. If anything is amiss, like one track failing, it throws all those crazy codes.

 

All the Garage found wrong was the air intake duct was adrift?
Fingers crossed it just doesn't stop again.
Thanks for all the advice.

 

Welcome to the forum Nick,

There may be other faults with engine management but this is a fundamental power supply issue. Apart from a suspect battery (which is always the first thing to eliminate on these cars), one common cause of the Instrument Pack lights coming on but the engine not turning over is loose connections in the HPPM (High Power Protection Module):



The connections can slacken or the terminal ends break up.

Graham