HELP ^%#&^@% CAR WILL NOT IDLE

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Mar 25, 2005 | 10:36 PM

M.Clough

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Joined: Feb 2005

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From: york pa

HELP ^%#&^@% CAR WILL NOT IDLE

This winter i did some work on my 85.Started the car car starts fine but after 45 secs. to 1 min. the car starts to carry on kindof like a miss
1.eliminated all emissions from the car.
2.removed cruise control from car.
3.removed cold start valve from car
4.elimated all un used connectors from wire harness(cold start lead,air pump leads,ac compressor lead
5.installed msd8.5 wires
6.installed ford 24lb injectors
7.eliminated pcv and run a breather in both valve covers
8.new ngk plugs

I installed a fuel pressure gauge i only see 31 lbs pressure could that be the problem.I hope it's something easy

Mar 26, 2005 | 02:56 AM

bogus

Team Owner

Joined: Aug 2000

Posts: 40,156

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From: San Pedro CA

31 PSI is low...

However, do you have any vacuum leaks???

Mar 26, 2005 | 07:59 AM

M.Clough

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From: york pa

i dont think so the only vacum im pulling is for the fuel pressure regulator.

Mar 26, 2005 | 10:39 AM

LaVidaLoca

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Joined: Jul 2002

Posts: 729

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From: Yukon OK

Idle is not a simple subject.

One check for you is to manually push the butterfly valves on the throttle body closed. If the idle drops you are dealing with a worn shaft. A way to confirm this is that the shaft is smooth and returns smoothly whent the engine is off, but sticks and won't return completely when the engine is running.

I did not look your year, but all these things contributed to my idle problem on my 85 which is now fixed;

IAC
Timing
Throttle body
Injectors leaking
Vacuum leaks
Throttle cable sticking

Mar 28, 2005 | 10:17 PM

M.Clough

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Joined: Feb 2005

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From: york pa

still stuck any thoughts?I need help i think i've rulled out vac. leak but not sure i looked over the gaskets the only place i have vaccum hook ups are fuel pressure regulater,pcv,and brakes.I plugged the other vaccum port in the regulator and throttle body.

Mar 29, 2005 | 12:39 AM

vettenut85

Instructor

Joined: May 2004

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From: machesney park il

reinstall the pcv.the pcv is needed to evacuate the crankcase gasses,this helps the engine

Mar 29, 2005 | 01:06 AM

500hp

Burning Brakes

Joined: Nov 2004

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31 PSI is to low for fuel pressure. Whether it improves idle or not (it should help some) you should probably install an adjustable regulator and set it around 40 to 45 PSI (anything under 35 PSI is not atomizing pump gas properly). What kind of PROM/chip are you running. It should be custom programmed with all your mods taken into consideration. When you change injector size on a GM, you usually need to tweak the computer's injector pulse width. If your computer thinks you have a smaller injector, it will be programmed to have a wider pulse width. A wider pulse width, with a larger injector, and lower fuel pressure equals alot of gas dribbling instead of spraying from the injector. Once into closed loop, the idle speed comes down, but the fuel keeps on flowing, leading to an overly rich, unstable and erratic idle.

Mar 29, 2005 | 08:49 PM

M.Clough

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From: york pa

i think i found the problem.Ford injectors have two notches for clips to hold them in the fuel rail.I used the wrong ones so my vacum leak was past the o-rings in the lower intake.I have to wait fro new gaskets on Wed. hopefully that will cure it