Rough Idle at Start
Thread Starter
Pro
Joined: Jun 2007
Posts: 647
Likes: 135
From: Big Canoe Georgia
Rough Idle at Start
Folks, I started my car yesterday and immediately the engine at idle was unusually rough, nothing like I have ever experienced before. Here is the background. Two days before I washed my car and immediately put it back in the garage. Fast forward two mornings later and I had the rough idle. It is a Z51 if that matters. After I drove off it drove fine. I parked my car and restarted it several hours later and no issues.
So could water get somewhere after a hand wash that could cause a rough idle on the first start if the car sat for a while after the wash?
So could water get somewhere after a hand wash that could cause a rough idle on the first start if the car sat for a while after the wash?
Safety Car
Joined: Jul 2018
Posts: 4,303
Likes: 2,055
From: Margate, FL
Could be a battery issue. If the battery isn't holding a charge then the problem might return if the car is started but not driven then sits again.
Unless you removed the hood vent duct a normal wash results in very little water in the engine compartment. Heck I've sprayed down my engine directly with water (low pressure of course) and it fires right up the next day with no issues
Unless you removed the hood vent duct a normal wash results in very little water in the engine compartment. Heck I've sprayed down my engine directly with water (low pressure of course) and it fires right up the next day with no issues
Melting Slicks
Joined: Mar 2001
Posts: 2,667
Likes: 849
From: New Jersey
Sometimes, if you cold-start an engine, and then only run it for a few seconds, and shut it off, the next time you cold-start it, it can have a spark miss due to fuel fouled plugs. The mixture enrichment from 2 cold-starts can sometimes temporarily foul a plug. I have experienced this problem with a few of my cars. Don't cold-start an engine and shut it off so quickly, let it run for 2 or 3 minutes.
Last edited by ersatz928; Jan 27, 2021 at 02:07 PM.
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