2001 XJR fault code please help
 

Hi I have just downloaded the following codes from my car I think it is the Lambda sensors that are at fault but if you can help that would be great. The car is running badly at tickover (misfiring) and lacks power ( it runs out of steam at about 135 mph were it should do 155mph)
P0300
P0301
P0302
P0303
P0304

P1316

P0420
P0430

P1000
P1113

P1647
If I am right and it is a Lambda sensor which one of the four is it.
Thanks for your help.:icon_steer:

Passed this a couple of times on my way down to XK8 section. Assuming your XJR will be the same DTC code set as my last 2001 XK8, here's the list:

P0300 = random misfire detected
P0301 = misfire on A1
P0302 = misfire on A2
P0303 = misfire on A3
P0304 = misfire on A4

P1316 = misfire excess emission

P0420 = catalyst efficiency below threshold on A bank
P0430 = catalyst efficiency below threshold on B bank

P1000 = drive cycle not completed since last code clear
P1113 = IATS 2 sensor low voltage

P1647 = ECM HO2S control malfunction B Bank upstream

Good luck.

Graham

Another thing that could cause a single bank issue is if the exhaust cam chain had skipped a tooth due to a failing tensioner. That would screw up the O2 sensor readings and cause the MAFS/ECM to over compensate causing the B bank issue.

+1

Good point.

Any doubts on tensioners and you need to be more worried about moving the next 135 feet than you do about investigating performance beyond 135 mph.

Graham

Thanks for that I know it is not the tensioners as it is a late model engine with the uprated tensioners, so any other ideas would be welcome, so I would be open to any other suggestions.