idle basics
Thread Starter
Drifting
Joined: Dec 2012
Posts: 1,504
Likes: 73
From: Georgetown TX
idle basics
what would be the reasons an engine rpm hunts very slightly at idle and has a misfire. I can not pin it down to one certain cylinder.
Is it too little air, too much air, too little fuel, too much fuel? I am reading between 133 and 135 in cell 00 at idle, which means a little lean, but I don't think its enough to cause it.
I can't figure out why mine does it. Its been doing it for years, and I can't find a reson. I think I have it down to ecu tuning problem.
I have tried EVERYTHING to find it, so its not electrial or adjustment of sensors, and not mech unless it had a cam installed before I got it, but I don't think so.
89 with auto, 52000 miles
Is it too little air, too much air, too little fuel, too much fuel? I am reading between 133 and 135 in cell 00 at idle, which means a little lean, but I don't think its enough to cause it.
I can't figure out why mine does it. Its been doing it for years, and I can't find a reson. I think I have it down to ecu tuning problem.
I have tried EVERYTHING to find it, so its not electrial or adjustment of sensors, and not mech unless it had a cam installed before I got it, but I don't think so.
89 with auto, 52000 miles
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Since IAC isn't changing I doubt its the ecm. If it's less than 50 rpm and random..myself i wouldn't worry about it. You can check you wires, plugs for condition and gap. Distributor cap and rotor for corrosion. Balance test injectors. Compression test.it can be a whole lot of work to verify nothing is really wrong. Worn motor mounts or belt driven accessories, missing, loose, or broken brackets can set a vibration. You could take it to a knowledgeable person and get their opinion.
