Morning all,

During my return journey from the east coast of Canada to the Toronto area this weekend, I developed a CEL with a P1316 (excessive emissions detected?) Code, P030x misfire codes for all cylinders and a random misfire code. Used my scanner to clear the code twice and it's come back twice. Drove the car for about 10 more hours/1000km after the code came on yesterday and performance does so far not appear to be affected in any way.

Have seen in other posts people discussing the injector driver module or perhaps tensioners. Of course, the car in question is my XJR-100, now at 160K miles!

Thoughts?

 

Does your scanner show a live data list? If it does, short and long term fuel trims is what you need to look for. Maybe even a coolant temperature reading also. If it doesn’t have a data list, start with the basics such as:

Check air intake tube around the bellows and at the TB.
Check and clean MAF sensor.
Check the air filter.
How long ago was the fuel filter done?

This injector driver module you spoke of is integrated in the ECM. I’m not saying the ECM isn’t bad but, highly unlikely.

I would be more inclined to check the grounds. The one at the battery and the one under the engine.

I’d also check the bulkhead connection behind the passenger side front shock tower for looseness.

 

Thanks for the reply. CEL persists through the remainder of the drive today. Air filter is brand new, I recently installed it along with the Mina intake. I checked all the fittings today and they seem snug, although I can remove and clean the MAF tomorrow. Fuel filter has been changed within the last 30K miles as well. Took some screenshots of the scanner readouts. See below:

 

The LTFT is still within spec but, it’s a tad high. I’d clean the MAF and perform a hard reset to see if the misfire codes (with no driveability issues) come back.

 

Cheers mate. Will do this later today and report back. Much appreciated.

 

Just wanted to respond to thank Addicted2Boost. Was traveling for 10 days and had the car parked. Been driving it often since I returned and the CEL hasn't returned. Hate leaving these threads unresolved, but for now - the problem has disappeared. Thanks again for the help!

David

 

Good deal!

Just to clarify, you cleaned the MAF and performed a hard reset? Or had you done something else as well to repair the issue?

 

Might also try a can of a good fuel system cleaner: BG44 or so. I don't remember: do the 2002 XJRs have the new style chains and tensioners? Sounds like a possible timing issue.

 

Didn't have the time to do any of it before I left for my trip! Since I've been back, the CEL hasn't come back on so I'm gonna chalk it up to gremlins

 

Yep, build date December 2001, so it's got all the new-style chains and tensioners

 

depends tbh

 

I had the same problem on a trip back in June, but worse. This was a 15-day trip to visit relatives and covered about 4,200 miles. I had some known electrical issues before starting the trip, but those were mostly on things like door modules and SCP circuits. The only consistent code affecting the ECU was P0460 for a short in the fuel gauge circuit. So, on day 3 of the trip I started getting the P0300 series of codes; sometimes all and sometimes two or three. That lasted all the way to day 15, then they quit showing up. On day five I got a P1112 code for the IAT sensor 2 circuit. Had to clear that one four times and haven't seen it since. I could go on and on about random codes all through the trip, but through all of this, the car ran great and I didn't have to call AAA. I had two scanners with me; an Innova 3160b and an Autel MX808, so I could see everything that was going on and clear codes as they popped up. When I got home I took my neighbor for a ride with the Autel plugged in. This guy used to be an Electrical Engineer for Mallory. He was looking at the scanner when I started the car and the first thing he said was, "Your alternator isn't working." The voltage showed 12.66 and didn't change when the engine was fired up. I put in a new alternator. All problems went away within a day. All door module codes, SCP codes, everything!

 

Get set of ignition coil from ebay back then when I bought it was 95$ I think today is like 120$ works great more than 2 years no issues