Hi

I had rough running on my 2000 XKR 4.0 so took it to the garage and they diagnosed it as the supercharger. It was sent away and rebuilt.

I have covered about 10 miles since and it has happened again and going into limp mode.

I don’t want to take it to the garage again due to a few reasons.

I have run a diagnostic check and have a number of codes. I was going to change the plugs and coils and the Maf sensor and see if it helps. However before I start chucking money there is there anything that I should do first that could be causing these, as it’s not just one cylinder.

codes:
P1316 Misfire rate excess emissions
P1638 CAN link engine control module/instrument cluster/network malfunction
P0207 Injector circuit malfunction cylinder 7
P0105 Manifold absolute pressure/barometric pressure circuit malfunction
P0307 Cylinder 7 misfire
P0303 Cylinder 3 misfire
P0300 Random misfire detected

Thanks

Neil

 

I have had a good half of those codes...and the first thing I would do are replace the coils and MAF. Find a high quality MAF sensor and good coils- may as well do spark plugs while you're at it. Follow up with a hard reset and go from there. Most always its these things that cause a cascading effect. Everything will run you about $300 which is what the dealership will charge you to diagnose anyways.
The second code you posted might go away with a hard reset, but to fix it you may have to replace the cluster or wiring between it and the ECU. Same with the manifold code. If not, it might have to be replaced as well. Also check the battery health! Good luck.

 

When replacing the MAF sensor for the 4.0 XKR’s or XJR’s, which all share the same unit, you are going to experience sticker shock.

those MAF’s are not common to any other car as far as my research can determine. The XK-8’s are more widely used and have a reasonable price

i tried several aftermarket units but none of them would keep the fuel trim numbers in an appropriate range. In other words, they were junk.

i gave up and bought one from a Jaguar dealer that had the best price. Apparently the Denso units are not being reproduced faithfully.

Other than needing an occasional cleaning its performed flawlessly.

 

Thanks

it had a new battery before it left the garage as it took so long to do the job the previous one was no good, so that should be ok. Could be the coms fault is prior to the battery change and needs clearing. I also used a different diagnostic tool that couldn’t read the car and the dash had all sort of faults scrolling. The latest diagnostic tool works fine and the dash is clear of faults, so could have been caused by the old diagnostic tool.

i would likely have gone for the aftermarket MAF sensor as the price is a lot better, so thanks for the advice. I will get a decent one.

 

I have found three wires from the left bank of coils which have damaged insulation on the loom that runs round the back of the engine. None were touching each other so might not have had any affect. It was covered with an extra layer of conduit so must have been like this for some time and covered up in the past. I will insulate them individually.