I had been battling a VERY intermittent misfire on my XTerra for a month or more, but it would only last a few seconds before correcting itself. Never long enough for the ECU to pick up which cylinder it was, so I never got a code. I thought I fixed it by replacing all 6 coils/plugs since it hadn't come back for several hundred miles so I took the truck on a 1,000+ mile camping trip last month. Of course it starts misfiring again in the middle of [censored] nowhere, and this time does NOT correct itself. Had to keep driving despite the flashing CEL because I'm in the middle of nowhere with no cell service even, get to the nearest town with a Nissan dealer who refuses to even look at it because they're booked solid, but I just happen to have my OBD2 scanner with me and this time it's identified it as cylinder 4. So I mess with the coil wiring and no more misfire. Loose connection is all it was
Of course I clear the misfire codes and pretty much immediately get a code for the cat. Truck feels off, like it has no power. I still have to pull my trailer 900-something miles home and that's a whole lot of fun especially in the mountains but I eventually make it and pull the cat off. Melted inside and plugging itself up, well that explains the code and lack of power. Truck is due for emissions testing in October and there are no aftermarket replacements that are legal in CA so my wallet is now $500 lighter
Of course I clear the misfire codes and pretty much immediately get a code for the cat. Truck feels off, like it has no power. I still have to pull my trailer 900-something miles home and that's a whole lot of fun especially in the mountains but I eventually make it and pull the cat off. Melted inside and plugging itself up, well that explains the code and lack of power. Truck is due for emissions testing in October and there are no aftermarket replacements that are legal in CA so my wallet is now $500 lighter
