Surging when first started
Thread Starter
TECH Fanatic
Joined: Jul 2005
Posts: 1,397
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From: Galesburg Il
Surging when first started My truck is running well except that for as long as I can remember the engine surges when it is started. It does not matter if it is warmed up or not if I shut it off to order at a drive thru window it has to go through it's surging thing.... revving to perhaps 2,000 rpm and back to 500 rpm, almost die and then surge again and this will go on for varying lengths, sometimes one or two surges and other times 6 or 8. I can't identify any condition existing to cause this and it drives me crazy. Any ideas?
TECH Resident
Joined: Jul 2007
Posts: 967
Likes: 53
From: Winter Haven FL
Which engine do you have? It sounds like a sensor issue but different engines have different sensors and programs so the info is important.
Generally what you describe is the engine overfueling on start which raises rpms and then the O2's read rich and cut fuel which causes a stumble. The overfueling is usually something like a bad temp sensor telling the ecu to raise the idle to warm up.
Generally what you describe is the engine overfueling on start which raises rpms and then the O2's read rich and cut fuel which causes a stumble. The overfueling is usually something like a bad temp sensor telling the ecu to raise the idle to warm up.
