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slight idle miss and running rich

2509 Views 4 Replies 3 Participants Last post by  Forklift
last night a few people were revving at the street races so I did a tad to give some rumble to the 4 cylinder croud. Right after I had a slight miss when it came back down in the rpms it had a miss. I left and had one problems all the way home, about 30 miles. This morning I got out there , started it up and no problem. I let it warm up a few seconds and revved it, nothing, revved it higher, nothing, revved it to about 4k and let it some back down and there it stumbled. I got out and I could smell gas and see the rick smoke coming out of it
any ideas?
Im thinking coil or fuel filter
I know Im slightly overdue for an oil change but is she mad at me for that?
before work today Im going to get some Seafoam for it. At 118,180 I think its time to get some interior engine cleaning done. I was going to do the oil and fuel filter this morning but rain woke me up at about 5am and it didnt stop till a few minutes ago so its soaked outside
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Usually I attribute a miss on my truck to the ignition system. When was the last time you did cap/rotor?

Running rich could be the 02 sensor, is the SES light on?
brand new O2, mostly. A new one was in the glovebox when i got it. Cap and rotor only had a few k on them as well as the plugs and wires. I got it about 8 months and 6-7k ago
Might want to check for cracks in the magnet on the distributor shaft. That can cause an intermittent misfire. if you pull the cap and rotor off you will see the magnet that goes around the shaft.

Also, look for arcing when it is dark, when you rev it it may provide enough KV for it to jump somewhere other than the spark plug. Check for a crack in the dist cap too. Ideally if you ahve access to a scope you can see which cylinder is missing and narrow it down. You could also pull the plugs and see if one looks like it is fouled out at all.
yeah I was thinking about most of that except the magnet thing
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