Soldato
I've been getting persistent P0171 and P0174 "too lean" codes on my Jag XJ with the 4.2 engine. It runs fine, but the EML is illuminated.
I initially went around the engine bay, spraying all the pipework and joints with carb cleaner and monitored the short term fuel trims. I noticed that the values changed significantly when I sprayed around the PCV valve and pipework, so I ordered new ones. I fitted those parts, but although the fuel trims now don't change when I spray around that area, I've still got the same codes coming up.
I tried using a cigar to smoke out the leak, but I couldn't see anything obvious. I noticed that the lid of the air box was slightly loose, so I reseated it, but again I can't imagine that would cause it, as it's before the MAF sensor. These are the values at idle with the engine fully warmed up. Is there anything that looks suspect here? I forgot to screenshot the long term fuel trims, but they're around 10-15% at warm idle.
Thanks
I initially went around the engine bay, spraying all the pipework and joints with carb cleaner and monitored the short term fuel trims. I noticed that the values changed significantly when I sprayed around the PCV valve and pipework, so I ordered new ones. I fitted those parts, but although the fuel trims now don't change when I spray around that area, I've still got the same codes coming up.
I tried using a cigar to smoke out the leak, but I couldn't see anything obvious. I noticed that the lid of the air box was slightly loose, so I reseated it, but again I can't imagine that would cause it, as it's before the MAF sensor. These are the values at idle with the engine fully warmed up. Is there anything that looks suspect here? I forgot to screenshot the long term fuel trims, but they're around 10-15% at warm idle.
Thanks