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12-06-2010, 11:08 AM | #1 |
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is this the idle screw of my Quadrajet?
is this the idle screw of my Quadrajet?
for some reason I need to hit the geaspedal once firmly and rev it, before the engine will idle at the correct rpm. Before that it will idle a little fast. any advise?
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12-06-2010, 11:20 AM | #2 |
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Re: is this the idle screw of my Quadrajet?
The high idle is when you first start it right? If so, that is normal and giving it gas will kick it out of the high idle is all part of the design of the carb and most other carbs as far as I know.
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12-06-2010, 12:45 PM | #3 |
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Re: is this the idle screw of my Quadrajet?
Yes thats the idle screw. But if your electric choke is working properly it will automatically start and go to high idle. once revved it will drop down to normal idle. It sounds like your have a properly functioning carb. But yes that is the idle screw
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12-06-2010, 12:46 PM | #4 |
Cruzzzn' Vet
Join Date: Jan 2005
Location: Porterville,Ca.
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Re: is this the idle screw of my Quadrajet?
It's the CHOKE that is making it idle high when you first start, giving the throttle a quik blip wil kick it off the high idle cam and return to idle speed once she's warmed up, and the screw you have circled is for idle speed adjustment.
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12-06-2010, 03:08 PM | #5 |
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Re: is this the idle screw of my Quadrajet?
thanks for all the reply's guys, but who was talking about first start?
not me... It is all the time, from first start, till normal operating temperatures...when bring the car to a stop, it will idle a little higher...until I tap the gaspedal and it will go down to normal idle speed. I started to notice this, when I recently set the timing for the ignition for the first time. I found it was set to "0" BTDC and I have now set it to -11 BTDC. This is about 4 degrees more, because I drive LPG. But ever since I set this timing, I have noticed this behavior...please advise.
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12-06-2010, 05:01 PM | #6 |
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Re: is this the idle screw of my Quadrajet?
If it will idle down to the proper rpm then adjusting it isn't going to help , sounds like maybe worn springs , maybe some crap build up or just plain wear on the bushings and that's holding the butterflies open a little and when you hit the throttle and release right away that is enough to pull it closed.Get some cleaner and spray all your linkages good and hopefully that will take care of it
Last edited by ont_guy_38; 12-06-2010 at 05:38 PM. |
12-07-2010, 05:18 AM | #7 |
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Re: is this the idle screw of my Quadrajet?
thanks for all the answers.
I looked at the picture again 2nite and saw that the cable for the cruise control in the front is pretty tight (is that the right word?). the CC is not working yet, so I am gonna remove that 2nite and see if it will go down to regular idle immediatley...thanks so far guys. I'll be back!
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12-07-2010, 01:53 PM | #8 |
Chris
Join Date: Nov 2004
Location: Monaville, WV
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Re: is this the idle screw of my Quadrajet?
usually if it idles high until you tap the pedal, the throttle linkage is hanging up on something, most likely a weak return spring, might need a new stiffer one. it'll make the pedal harder to push down but it wil lreturn it to correct idle.
If you tap the gas and it idles right then the screw doesn't need adjusted. Find another spring and try it. Dad's 84 with quadrajet done the same thing, it would actually pull itself down the road about 30 mph. We changed the spring for a stiffer one and it worked fine. The choke could be sticking too making it do that, but for us ours was unhooked and wired open.
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