Hi, I have a XK8 2001 coupe, that misfires around the 40 / 50 MPH range. I have had extensive work done to solve the issue (2000Euro is costs) but my Jag guy is scratching his head as everything he has tried has failed.
This started out of the blue, no prior issues, like I had been driving parked up, then next day I have the problem. I did unfortunately let the fuel run too low before filling up, but my guy checked out possible issues with that.
Has anyone had a similar problem
Thanks
Gordon.

 

What codes do you get when it misfiring?

 

Hi, thanks for replying, I cant give you info right now. However My Jag guy was getting some very strange codes that didn't make sense. We sent the ECU away for checking. When we got it back it gave different strange codes. Sent it back again thinking it was not fixed correctly. Turns out nothing wrong with ECU. I will be going on Monday to see my guy. I will then post the latest info on the codes and a more detailed description of work done.
Thanks again for replying.
GOJE

 

Get yourself an OBD reader and the Torque app, then you can read the codes yourself. If your Jag guy doesn't understand the codes, that isn't a good sign.

 

Hi, probably I didn't explain well about the codes, but yes I will get my own OBD im just looking now at the extensive range available wow.
I will get back with clearer details and appreciate all help and advice.
Thanks
GOJE

 

Has your guy checked the fuel pump is producing sufficient fuel pressure at higher revs? The fuel pump is rather fragile in the x100 and there is only one and misfires across a few cylinders would be a typical symptom of a failing pump.

Richard

 

Hi,
just got the car back home. still in bad shape. Ok I got the OBD. wasn't sure which to get, but after reading some posts and scanning the web I went for the Autel 519.
This came up with the code PO301. Cylinder 1 misfire.
Work done so far to solve the issue. My jag guy uses Texa computer set up.. which could not determine or gain information form the ECU. this was sent for inspection and was repaired . However it still didn't pinpoint the issue. It read multiple misfire on cylinders 1/2/3/4 Bank 1 too rich 02 sensor circuit high voltage bank 1 Replaced. Plugs and coils all ok.
Compression test on all cylinders readings of 175 / 180psi. Injectors removed and tested all ok. Smoke test on intake manifold found fault with vacuum conector to brake servo. Replaced. Intermiten faults with air flow meter. new one fitted. Fuel pressure test ok. Intake manifold gaskets and injectors cleaned.
Being a novice and only learning via internet I found a idiots step by step guide to PO301. Going through the list of causes . catalytic converter this was checked and showed no issues. Also mentions the crankshaft sensor.. not sure if Simon looked at that, but Im going call him later when I have finished reading through some more suggestions.
Regards
GOJE
Just had anther check and now I have PO300 random / multiple cylinder misfire detected. I like like this tool . guide to what to check. looks like I need to go over everything that's already been done. Its possible I guess something has been overlooked of not checked correctly.
I came across a post relating to my issue. It was saying that the cam timing chain may have jumped a tooth. I also came across an article on the internet, that suggests disconnecting the sensor and restart the car. If it doesn't shut down in 5 seconds it suggest that indeed it could be the chain. Would that correct ?

 

2001 XKR’s have 2 fuel pumps

 

something else to check which isn't obvious or called out - the wiring harness to the coils. Was getting multiple misfires on mine - replace coils, plugs, injectors tested, etc. But when putting back on, noticed the insulation on the leads in the wiring harness to the coils was flaking off - exposing the copper wires with several contacting each other at these points. As a temp fix, I wrapped each damaged lead with electrical tape and spurious multiple misfires have ceased

 

HI, Thanks for info and help appreciate it.