Hi can anyone tell me if my throttle position sensor or my crankshaft position sensor (or any other sensor) would cause a stalling problem on my 97 XJ6 without generating a code? It seems to happen every time I run the car for more than about 25 minutes. I can be driving 50 MPH or sitting at idle it doesn't matter. Seems to me to be electrical, maybe a bad sensor or ECM. I just bought the car and discovered this problem.

Thanks,
Pat

 

The ckps, the one on the front crank damper is a known intermittent fail problem. HArd to believe the TPS would stall at speed.

 

leaning towards crank sensor on that one.

/agree with spark

 

ECM relay

 

Replaced the ECM relay. Will now move on to the CPS. Found out I have a bad air/smog pump also and when it tries to kick on the fuse blows and car stalls or almost stalls.

 

that seems such an odd issue.

I've never seen the air pump cause issues.

will it run without the pump active?

 

It will run for short periods of time and then stall or try to stall. I'm able to keep it running by applying throttle. Don't know if the pump is causing the car to stall or if the car stallnig is causing the pump to short out. I'm beginning to think it's a bad ECM since I'm getting no codes.

 

I had an XK8 in my shop once that had 68 engine trouble codes.
it had a bad ECM.

odd that you wouldn't get a check engine light even for a few moments as I'd think the air pump failure would cause a lean condition not unlike vacuum leaks.

 

At the risk of starting a "discussion" I will make the observation that the X300s are pretty hit and miss for codes. A friends car would only occaisonally give a TPS fault, even with the sensor unplugged. It ranlike crap, but is A-OK with a new TPS.

 

that is true

 

Chech harness connector at ECM (RF footwell outer). They get wet and rot terminal connections

 

Put in a new ECM & TCM and the connectors seemed clean and dry. Now I'm getting a racing motor in park up to 4K RPM's and have to keep my foot on the brake to stay below 50 MPH when I'm driving and I'm still having electrical problem where all of the dash lights come on for a few seconds and then go out. I am now thoroughly confused.

 

Hi, My guess it's the "Crank dwell angle", happened to me, in fact, I became quite good at breaking with my left foot to allow me to put revs up with the right foot at lights etc.

Best of luck