idle problem
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 949
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From: smithtown ny
idle problem
i have a 91 vette when the car goes into closed loop it idles low and idles rough i have a new fuel pump and a new adjustable regulator the car has 80,000 miles if i pressurize the fuel shut the car off the fuel pressure goes from 42psi to 15psi in 10mins when the car is warmed up if i hold the gas to the floor it will start right up also what is the stock injector size can any one tell me if it's time for new injectors thanks
Le Mans Master
Joined: Apr 2000
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From: DrunkDefender
CI 1-2-3-4-5-6-7-8 Veteran
CI-IV AutoX Champ
CI-IV Burnout Champ
St. Jude Donor '07-'10
Re: idle problem (6spd)
If your fuel pressure is dropping to 15 psi while the car is running I'm surprised it's still running. Sound slike a fuel pump or a fuel filter stopped up. Stock injectors are 22lbs. Your FP should not drop below 40psi but I have seen some run 38 but any lower and I'd lay money on it being a fuel pump or filter.
Pro
Joined: Jun 2001
Posts: 509
Likes: 5
From: Edmonds WA
Re: idle problem (6spd)
I can't speak on the fuel pressure aspect of things, but consider checking out your idle (IAC) valve. Mine behaved similarly, although usually on startup, where I had to put the pedal down partway to get it to start. I could drive it, but it would idle low and rough at stops. I took apart the TB and repalced the IAC valve and haven't had any trouble since. You could at the very least clean up the IAC some (mine was pretty cruddy when I pulled it out).
Best of luck with solving the problem... sounds like yours is consistent; mine was a bitch because it was intermittent.
Best of luck with solving the problem... sounds like yours is consistent; mine was a bitch because it was intermittent.
