I mean does it actually monitor the ignition system or can an issue with a fuel injector cause this to also set off the monitor?
I have a 2003 Baja 2.5 non turbo, 5 speed with 62,000 miles on it and all of a sudden within the last couple of days I noticed the engine idles rough on a cold start.
Then at times even after the engine has reached normal operating temperature, I can feel it misfiring at idle and even see the RPMS drop when this happens. And I can feel it under slight accelaration sometimes.
This morning after getting off work I started the car and allowed it to warm up because it was so humid my windows kept fogging up on the inside. After a couple of mnutes the check engine light came on.
When I got home, I plugged my code reader in and it said the engine monitor detected a #1 misfire. I cleared the code and restarted the engine. The check engine light never came back on.
This afternoon, I started the engine and it started rough again and was around 75F instead of 40F this morning and it misfired at redlights on the way to Wal-Mart even after the engine had already warmed up. But the check engine light never came on. After leaving Wal-Mart and onto work it I never noticed anymore misfires.
It seems to be a randomly occuring event with no particular pattern.
But this isn't the first time this has happened.
This time four years ago the check engine light kicked on as I was driving down my driveway. Then before pulling out onto the road, all of a sudden it went off.
Highly unusual that the check engine light would go off on it's own. With other cars I've always had to disconnect the battery for 30 minutes or have Autozone reset the ECU to get the light to turn off. And usually it comes back on with 30 seconds.
I took it to the dealer to get it's 30K mile checkup and told them about it. They said the ECU stored a #2 misfire code and they said they cleaned some corrosion off the plug wire.
Supposably they also installed new spark plugs but not new wires. Are new plugs part of the 30K mile checkup?
A few months ago at 60K miles I pulled the plugs and they looked good. I beadblasted and regapped them anyway and put them back in. Maybe the cheap way of doing it but I've done it on other cars and lawnmowers I've owned.
I'm just curious is it common for an 8 year old Subaru to need new plugs or plug wires this soon? Usually a set of plug wires are good for about 100K miles.
I think the cheapest thing to start out with are new plugs, see what happens before installing new plug wires. Since they are not standard plug wires (extra long boots) they can't be resonable.
What I don't understand is the engine is obviously misfiring but the monitor has only detected it once in this latest eposide. Looks like if it's misfiring every 15 to 30 seconds, it would detect it more often.
Just wondering what my plan of attack should be. I guess if the plugs don't fix it, then try new plug wires and if that doesn't fix it, then suspect the coil pack perhaps?
Anybody have any experiences or opinions with this same issue? Thanks.
Edited by jseabolt, 14 April 2011 - 07:36 PM.