'85 350 no fast idle? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

JohnKimble · 11-06-2016, 10:13 PM

Hello,

First off let me start by saying I have an '85 with a 350 and California emissions package

Now that the weather is getting colder I've noticed my choke remains open, even after leaving it overnight in the cold. It still starts up fine, but does not idle any faster when cold vs. warm. Did this truck come with a fast idle cam? If so, should I be able to kick it down with a blip of the throttle after the initial cold start?

Thanks!

geezer#99 · 11-07-2016, 12:55 AM

Assuming it's a quadrajet with an electric choke, just richen the choke setting. Rotate the black cap ccw. There's three screws that hold it on. There's a high idle screw under the choke pull off pot. Hard to see but just needs a phillips to turn it.
Kicking it down depends on how rich it is and how quick it warms up.

JohnKimble · 11-07-2016, 01:08 AM

Thank you, I will attempt this tomorrow.

JohnKimble · 11-07-2016, 04:21 PM

Quote:

Originally Posted by geezer#99

Assuming it's a quadrajet with an electric choke, just richen the choke setting. Rotate the black cap ccw. There's three screws that hold it on. There's a high idle screw under the choke pull off pot. Hard to see but just needs a phillips to turn it.
Kicking it down depends on how rich it is and how quick it warms up.

I just tried to rotate my choke cap ccw. It won't do anything. I can't close the choke plate manually, the linkage is firm and refuses to budge. Any suggestions?

geezer#99 · 11-07-2016, 04:53 PM

Take a pic!!
Is it screwed or riveted on?

JohnKimble · 11-07-2016, 04:55 PM

Okay I got the choke plate to close and cap adjusted correctly. Onto the fast idle issue:

I turn the truck on: Fast idle occurs. I blip the gas. Fast idle continues.

I manually press down on the fast idle cam and it kicks it down a step or two. Suggestions?

geezer#99 · 11-07-2016, 05:09 PM

Turn the cap again to lean it down. It's a compromise. You gotta experiment to find that sweet spot. You mighta gone too rich.
It's all a juggling act!!

I'm assuming this is an electric choke??

JohnKimble · 11-07-2016, 05:30 PM

Yes it's an electric choke. So I backed out the fast idle screw a little and cleaned it up. I blip the throttle and it kicks down! I'm sure the neighbors have been tired of hearing that thing idling so high at 4am. Thanks for your help #99!

Fast idle and choke fixed!

11-06-2016, 10:13 PM	#1
JohnKimble Registered User Join Date: May 2014 Location: CA Posts: 152	'85 350 no fast idle? Hello, First off let me start by saying I have an '85 with a 350 and California emissions package Now that the weather is getting colder I've noticed my choke remains open, even after leaving it overnight in the cold. It still starts up fine, but does not idle any faster when cold vs. warm. Did this truck come with a fast idle cam? If so, should I be able to kick it down with a blip of the throttle after the initial cold start? Thanks!

11-07-2016, 12:55 AM	#2
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,542	Re: '85 350 no fast idle? Assuming it's a quadrajet with an electric choke, just richen the choke setting. Rotate the black cap ccw. There's three screws that hold it on. There's a high idle screw under the choke pull off pot. Hard to see but just needs a phillips to turn it. Kicking it down depends on how rich it is and how quick it warms up.

11-07-2016, 01:08 AM	#3
JohnKimble Registered User Join Date: May 2014 Location: CA Posts: 152	Re: '85 350 no fast idle? Thank you, I will attempt this tomorrow.

11-07-2016, 04:53 PM	#5
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,542	Re: '85 350 no fast idle? Take a pic!! Is it screwed or riveted on?

11-07-2016, 04:55 PM	#6
JohnKimble Registered User Join Date: May 2014 Location: CA Posts: 152	Re: '85 350 no fast idle? Okay I got the choke plate to close and cap adjusted correctly. Onto the fast idle issue: I turn the truck on: Fast idle occurs. I blip the gas. Fast idle continues. I manually press down on the fast idle cam and it kicks it down a step or two. Suggestions?

11-07-2016, 05:09 PM	#7
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,542	Re: '85 350 no fast idle? Turn the cap again to lean it down. It's a compromise. You gotta experiment to find that sweet spot. You mighta gone too rich. It's all a juggling act!! I'm assuming this is an electric choke??

11-07-2016, 05:30 PM	#8
JohnKimble Registered User Join Date: May 2014 Location: CA Posts: 152	Re: '85 350 no fast idle? Yes it's an electric choke. So I backed out the fast idle screw a little and cleaned it up. I blip the throttle and it kicks down! I'm sure the neighbors have been tired of hearing that thing idling so high at 4am. Thanks for your help #99! Fast idle and choke fixed!



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