idle speed screw question
03-27-2003, 07:49 PM
#1
Three Wheelin'
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idle speed screw question
With the idled stabilizer jumped out, how low will your cars idle with the screw turned in all the way?? I'm idling about 850 rpm, and I end up turning the screw out about 1/4 to 1/2 turn to set idle at the point when the idle stabilizer would hold it ( a hair under 1000 rpm on the stock tach) I'm still wondering if I have a vac leak somewhere.
03-27-2003, 10:33 PM
#2
Nordschleife Master
I can get mine to drop to like 300rpm with the screw turned all the way in and the idle stabilizer disabled...vac leak is possible, try putting your finger over the hole where the idle screw goes...there's an O-ring there that may be leaking...
03-28-2003, 08:23 AM
#3
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After the fire I replaced all of the vacuum lines and didn't know about the restrictor in one of the lines comming off of the venturi. I couldn't get the idle very low, something like what you are experiencing. I installed the restrictor and now I can, with the idle stabilizer jumped, get the engine to run at about 400 rpm by turning the idle adjuster screw in all the way.
I hope that this helps.
Steve Frew
'86 951 mostly stock.
I hope that this helps.
Steve Frew
'86 951 mostly stock.
03-28-2003, 08:58 AM
#4
Three Wheelin'
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I wondered about the restrictor, I can see the 'extra' clamp in the middle of the hose, so I assume its there.Does anyone hapen to know the diameter of the hole in the restrictor?? I plan on removing the intake soon and replace the hoses, this is juat one more indication that I do have a vac leak somewhere that I cant find when presure testing.
03-28-2003, 11:18 AM
#5
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I didn't measure the hole in the new restrictor that I installed but using the calibrated eyeball it seems to be about .030 .040 inch.
Steve Frew
'86 951 mostly stock and all fun!
Steve Frew
'86 951 mostly stock and all fun!
03-29-2003, 06:32 PM
#7
Three Wheelin'
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Well, I just removed the vacuum venturi and all its old, hard hoses and Plumbed the brake booster directly to the manifold. My car did have the restrictor, but I didnt use it when connecting the brakes to the manifold. After doing this, the idle would drop to 500 or so with the screw fully closed. I had to turn it out about 1 1/2 turns to get the idle back up.
I still have the part throttle hesitation tho. I'm about to say screw it and keep it on the ROW maps.
I still have the part throttle hesitation tho. I'm about to say screw it and keep it on the ROW maps.
