Crossing fingers! New OEM replacement gas cap arrived, installed. Cel light went off minutes later. Filled gas tank. Some forty miles later — no restricted performance nor CEL light yet!! Could it be?

Replacement fuel filter is on its way via UPS!

thanks all, for the suggestions and input. I will keep you posted. Meanwhile, the crossed fingers are starting to cramp.

 

That's great news Bill! Keep us posted on whether this was truly the fix. May I suggest that you hold off on installing the new fuel filter for a month or two or unless/until the problem recurs? That way we'll all truly know if the gas cap alone was the culprit. Do you hear the whoosh when you open the cap now?

 

You listed P1000 before. It means one (or more) OBDII monitors did not complete. It would help to know which one failed to complete (likely EVAP at this point). You need to get P1111, meaning all monitors completed.

You can also check if there are pending codes. Some codes take 2 trips to show a check-engine light. This is all standard OBDII stuff, no need for Jaguar-aware tools.

Separately, you need a fuel filter with quick-connect fittings, not barbs. Somehow, our cars are cataloged to require the old barb style, which is incorrect. You can check against the 4.2L S-Type part# (which is what you need).

 

Hello Bill,
I remember having what sound like very similar problems to yours. In my case it turned out to be a coil failing. Once the coil was identified and replaced all was good.
Regards, OZXK8

 

I am having issues with my OBDII scanner, it is not connecting on the OBDII scan but works on other scans. I will run to AutoZone to get them to check for the P1111 code. I did drive another 100 miles without any CEL or RP lights. The fuel filter I ordered is a Mahle KL83. Is this the correct one?

thanks for your help

Bill

 

That fitting looks good, but it comes out as an x-type part. KL181 would be better (s-type 4.2).

If you don't have one already, get a cheap ELM327 for everything OBDII related...

 

I found this today which might be the explanation for why the CEL came on when the tank was full and why the new cap appears to have fixed the problem:
From the Youcanic.com site re: Jaguar CEL troubleshooting - Loose Gas Cap:

"It (the loose gas cap) causes fuel fume leaks that the onboard system will detect, causing a lit CEL. There have also been cases where a full tank sets off error codes in the evaporative system, also causing Jaguar check engine light to come on."

You mentioned you didn't hear the 'whoosh' when opening the cap which might indicate the seal had worn to the point where the cap was allowing fumes to leak. Hope that's all it was!

 

Well, the crossed fingers failed! Just got the Restricted Performance light then shortly thereafter the CEL light! So the gas cap does not solve the issue! When the fuel filter comes in I will install it and proceed with the other suggestions by Fmertz. Then onto the knock sensors.



EZDRIVER what is your secret to changing the Knock sensors without removing the intake manifold?

Ok new development! CEL light came on as mentioned. I ran OBDII and got knock sensors code - actually two! Frustrated I went into my office to finish some work.

Few hours later, “beautiful early evening, I came out, cranked the car. CEL light of course stayed on. I lowered the top for my drive home — it had been raining. Top was up when the RP and then CEL lights came on.,

Heading down the street with the wind blowing in my hair, the CEL light suddenly goes out!

Is she trying to tell me she is happier topless!

 

No whoosh sound when opening the new gas cap. Could that be the sign of a vacuum leak elsewhere? After my CEL light suddenly turned off Friday evening it came on again Saturday morning after the RP light showed its ugly head for a few seconds. Interestingly enough the RP light came on at low speed or while idling and quickly disappeared when the engine speed picked up. Suggestions?

I have inspected vacuum lines both around the charcoal canisters as well as in the engine compartment — all look good.

I am am awaiting my fuel filter to arrive tomorrow, will install, add the Techron gas additive to clean the injectors and such.

After the CEL lights came on I checked the codes — still getting P0328 and P1000 codes, no P0191 code sine I cleared the codes on August 1st. Just double checked the codes, then cleared them. Scanner asked if I wanted to clear the EVP codes which I did and of course the CEL light went off. What does it mean by the EVP codes?

 

Bill,

Basically EVP refers to the EVAP system in our car where fuel fuels are controlled via the charcoal canisters and released via a valve into the engine to burn. See pic below. This is monitored by the car, and there are dedicated P04xx DTCs that may help diagnose the problem.



Can you confirm that the CEL and Restricted Performance only occurs at low speed. At high speeds, you don't have an issue? If you're not seeing any P04xx DTCs, the EVAP system probably ok, and I would investigate your DTCs on the knock sensors. Did this occur on both banks at the same time?

 

Ok, I have my new fuel filter, read all of the instructions in the XK8 Bible as well as the workshop Manuel on how to remove and replace. Got the old filter disconnected from the car via the 10mm nut. Easy enough! However disconnecting the top and bottom quick connect connectors isn’t going as easy. I am pressing the “tangs” as instructed without success. What is the secret???

 

Try and find some spray cleaner to loosen any dirt, the "tang" is white. Resist the urge to use a tool, it is supposed to be handled manually (unless you have something very dull and soft like a plastic tool). The white section pushes right in and slides perpendicular to the filter pipe. Maybe try and push the fitting in (towards the filter) to reduce the pressure on the slider. This is easy to overthink and get frustrated with this fitting.

Best of luck, keep us posted.

 

Thanks!!!
Sprayed both down. The white button on the bottom one pushed down but does not seem to want to slide perpendicular to filter. Am I reading that correctly?

 

Yep, the tang slides perpendicular to the filter pipe, then it frees the fitting to slide parallel to the pipe.

 

Got it done! Really simple — once you know what you are doing! Old filter appears to be the original in that is is a Jaguar filter but I have never see such black colored gas that drained out of it! Black as used oil! The new filter has to improve something. Next is the Techron treatment.

Hopefully this too stops the knock sensor code. My guess is it won’t so does that mean the knock sensor is bad and needs replacing? This being a 4.2 engine is there a way to replace without removing the intake manifold?

again thanks to all especially, fmertz!

 

If you can safely do so, try and have the pump dump some gas from the supply line to the filter before buttoning everything up. Check the gas comes out clear. Gas tanks can get nasty over time.

 

Gas dripping from the tank line seemed to clear. Same for gas dripping from the bottom line going to the engine. It was just gas coming from the inlet side of the filter that was black.

 

Good news! After replacing the fuel filter yesterday, we went on a 120 mile trip. With the exception of a Restricted Performance light at the very beginning of the trip - the car had again been idling for a period but went off after we got up to speed — no other lights!

checked the OBDII scanner a few minutes ago and only found the P1000 code. No engine knock code for the first time! Does this suggest my knock sensors are good and my fuel filter was the real culprit?


Bill

 

Actually, you need P1111. This is where you need to find the part of the OBD scanner that gives you the status of the individual monitors (this is standard stuff, not Jaguar specific). There are several of them, and they all need to reach a completed status. Each have their pre-requisites and each one have their own requirements (it is the OBD drive cycle). Some usually complete quickly on their own (cats, O2), some are more of a bear for some cars (component, evap).

 

Still working on the P1111 code. Reread the instructions, ran scanner through ever test possible — no P1111 code just P1000. Unfortunately, this afternoon the CEL light came back on after accelerating on to highway. Yep it is the knock code. Then started getting the RP code when driving slowly.