1994 with random rought idle
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1994 with random rought idle
Have a 1994 with the base LT1 engine. Problem: a rough idle. The issue is the rough idle is random, i.e., it comes and goes. Seen much info as to the cause of a rough idle and I have “chased” them all. However, I have not seen any info re: an inconsistent rough idle. There is no rhyme or reason as to when it comes and goes, i.e., engine cold or at operating temperature, in the morning or after driving for quite a while during the day, etc. For example, engine running smooth, stop at a red light and have a rough idle. The rough idle condition can last for a short time or a day or two. Then like magic crank the car and have a smooth idle. Issue is like chasing ghosts. If anyone has any ideas as to what could be the potential problem any and all suggestions appreciated. Thanks Bob
Drifting
Joined: Feb 2016
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From: Simi Valley CA
I always feel problems like that aren't with parts going bad and then all of a sudden fixing themselves and then going bad again. Its usually poor electrical connections. There are solder points in the ecm that go bad and sometimes connects, sometimes don't. Electrical plugs sometimes wiggle and make better connections. I've had issues with charging systems on cars as old as a 67 Mustang that ended up just being dirty connections. So these cars with millions of more wires are prone to these issues.
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1994 with random rought idle Reply to Thread
I always feel problems like that aren't with parts going bad and then all of a sudden fixing themselves and then going bad again. Its usually poor electrical connections. There are solder points in the ecm that go bad and sometimes connects, sometimes don't. Electrical plugs sometimes wiggle and make better connections. I've had issues with charging systems on cars as old as a 67 Mustang that ended up just being dirty connections. So these cars with millions of more wires are prone to these issues.
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1994 with random rought idle
Two questions. 1. How do you know? and 2. Is it the Engine Coolant Temperature (ECT) Sensor? Got an ODB code PO118 a couple years ago and replaced this sensor. Thanks and waiting to hear the answer as to "How do you know".
Drifting
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From: Plainfield IN
