stroud13
Member
- Joined
- June 12, 2001
- Messages
- 24
- Reaction score
- 0
- City, State
- Wichita KS
- Year, Model & Trim Level
- 1991 XLT
I have a '91, 4.0L, 4door, 2WD, 116K. I have been experiencing intermitten run-on for several weeks now. I checked the normal things - wires, plugs, MAF sensor - but couldn't track down the source. It seems to occur most during hot weather.
I took it in to a shop(mistake). They changed the plugs (the other ones had 10K on them)- said one was fouled badly and one was burnt...I'm sure that's caused by the run-on, but not the source. Anyway, it ran fine for two days - and now the same old problem.
Does anyone know what I should check next? I've heard of leaky heads causing poor mixture and fouling, but I can't find any info. I'm going to clean the MAF again and check/change the plugs again if bad.
What about clogged CAT, or carbon build-up on the pistons? Any ideas?
I took it in to a shop(mistake). They changed the plugs (the other ones had 10K on them)- said one was fouled badly and one was burnt...I'm sure that's caused by the run-on, but not the source. Anyway, it ran fine for two days - and now the same old problem.
Does anyone know what I should check next? I've heard of leaky heads causing poor mixture and fouling, but I can't find any info. I'm going to clean the MAF again and check/change the plugs again if bad.
What about clogged CAT, or carbon build-up on the pistons? Any ideas?
