Four times during a 15 min. drive to a friends house the XK8 engine lost power but came back when I hit the gas pedal. Flashed Engine Fault briefly. On the return trip it ran perfectly and the Autoenginuity found no stored codes, and the battery is fine.
Next time I take it out I will have the Ultragauge connected to see if anything is funny with tps or fuel trims.
Meanwhile would appreciate any thoughts.

 

First thing to do, if you haven't done it recently: the throttle body can get dirty and cause the butterfly valve to stick in certain conditions and cause a stall. It's fairly common and you'll find multiple threads discussing it.

Happened to me at highway speed...in the left lane, of course.

Anyway, a thorough cleaning with CRC Throttle Body Cleaner or an equivalent may be all you need. Be sure to clean not only the throttle body bore, but also the edges of the butterfly valve and its hinges.

Good luck.


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It looks like the fuel pump died. I took it out today and displayed Engine Fault and Reduced Performance after five minutes. I got it home, barely making it up the hills, and parked it in the road while I went down and moved the other car off the lift. It died there and the schrader valve is not putting much out. The engine starts but shuts off immediately. This afternoon I'll get some help moving it into my garage and check further.

 

This is getting complicated. I was able to start the car and get it into the garage, but it still had the reduced performance message. Autoenginuity codes were P0351,2,3,4&6, not what I expected. Cleared the codes and started engine. It ran fine for a minute, then went into reduced performance, but no codes found, not even P1000. After shutting off I ran codes again and got P0351,4,&6, still no P1000. I'm beginning to suspect the ECU.
Tomorrow I'll pick up a fuel pressure tester. I was going to start the tank removal, but think I'll wait.

 

check the fuel filter if you get a low reading on the fuel pressure tester.

 

Fuel pressure is 40 whether engine is running good or bad. I checked the codes with the Ultragauge and found P0351,4 6&7. But also P1367 which the Autoenginuity did not display.
So it looks like an ignition problem, but I don't know where to go from here. Hopefully a forum search will help. The knowledge of others would be appreciated, as always.

 

I have read posts by Alan E L describing the same problems that I have. His were resolved by replacing the ECU with a rebuilt unit, so that is what I will probably do.

 

Problem resolved. I sent the ECU to ASI for repair. It was back in one week and road test was successful today. It would have been quicker if they had an exchange unit, but mine is a early model and not common. The repair has a 5 year warranty.

 

Glad to hear it...hopefully you'll be clear of these issues now, but do let us know if something pops up.


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