'86 Fuel Pressure
Thread Starter
Le Mans Master
Joined: Mar 2006
Posts: 5,262
Likes: 0
From: E. Amherst NY
'86 Fuel Pressure
I've been fighting this rough idle thing forever it seems. I just checked my fuel pressure.
Rock solid 42-44psi (vacuum hose off on the regulator) while running. But, turn the key to the on position, it pressurizes and then drops like a rock to 26psi and slowly bleeds from there. Same thing on shutoff. Am I on to something here?
Injectors are new this spring, Bosch Design IIIs.
Regulator bad?
Rock solid 42-44psi (vacuum hose off on the regulator) while running. But, turn the key to the on position, it pressurizes and then drops like a rock to 26psi and slowly bleeds from there. Same thing on shutoff. Am I on to something here?
Injectors are new this spring, Bosch Design IIIs.
Regulator bad?
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
I believe there is a check valve on the fuel pump that can cause this also, but if you are getting 42 lb running at idle not sure the drop in preassure after shut off would affect it. Have you tried cleaning the TB & IAC a lot of uneven idle conditions can be solved by doing that. Also some people have used SeaFoam to smooth out a rough idle due to carbon build up.
