1999 Jaguar Xk8 Convertible
Ran great up until two weeks ago, filled up with premium out of town. Car ran fine for ten miles and then began to miss and idle rough. Then it began to miss and chug upon reaching 55 mph and any time the engine is under a load (i.e. going up a steep hill). Now the CEL is on as well as the Restricted Performance amber light. Ran the codes:
P1313
P1316
P1000
P116
P125
P455
P301

Help! Love this car, just got all the taillight issues fixed and now this! Any help is greatly appreciated. I did change the fuel filter to no avail. The gas smelled bad, but I've gone through three tanks of gas since then.

 

You may 1st want to check your engine coolant temp sensor, P0116 and P0125 are pointing to an issue. But also the P0455 isn't good either, its related to the EVAP system, which is also inhibiting adaptive fuel metering. Both issues can certainly lead to the misfires.

 

I'll bet it's bad fuel.
Most of those codes are misfires with contaminated fuel listed as a cause.
The P1000 just means the diagnostic cycle hasn't completed.
I can't explain the codes Avos mentioned.
When did you last change the fuel filter ?

 

I changed the fuel filter in the return line under the car about a week after the RP popped up. The fuel smelled awful! But, I've gone through three tanks of fuel since then. Still have the problem, could bad fuel stick around that long? Any help is greatly appreciated.

 

Must be something else, I'd guess.
If you clear the codes do they ALL come back?
Another thought - have you looked at the plugs? If you got a bad lot of fuel it might have done them no good - easy to do and one item off the list.

 

I get P455 and P1000 frequently. Changed out the fuel cap and a couple sensors to the tune of about $600. Finally just bought a reader to clear the codes each time. It's really weird; I usually get the codes the day after I fill the tank.

 

Are you toping off the tank each fill? If so, try a short fill next time and see if you still get codes.

 

Depending on where you live you will not pass emissions testing on inspection if your state has one. They must see all Emissions settings passed selftest and complete. Resetting codes will reset these test complete indicators.

The problems most likely is the purge valve (inside driver side [us] fender well between tire and door). Do a search on purge valve there are some posts on this.

 

I'll take a look at the purge valve, thanks! If I clear the codes before the inspection it passes. Happened a couple years ago.

 

Wouldn't pass in many states as the OBD monitors would be unset by that.

 

As long as you see P1000 it's not going to pass, need to get P1111.

 

I looked back at my maintenance records. I have changed out the purge valve, gas cap, and canister vent closing valve. Still getting the P455 (with P1000 that I guess never clears). It used to happen only after a fill up; but now is happening more frequently. Any advice now?

 

A smoke test of the evap etc.