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-   -   '71 C10 Fast Idle Solenoid (https://67-72chevytrucks.com/vboard/showthread.php?t=518604)

BigRed76 04-08-2012 09:44 PM
'71 C10 Fast Idle Solenoid
 
1 Attachment(s)
On the right side of this picture is what I know as a fast idle solenoid. I know that when its plugged in it works, but it never shuts off to allow normal idle. I also noticed that there are two vacuum ports on the side of it that are not connected. Does anyone know how these are supposed to operate? Or is it not worth my time to mess with it?

Sport/Truck 04-08-2012 10:43 PM
Re: '71 C10 Fast Idle Solenoid
 
I think its the TCS solenoid, most remove it as it's not used/needed.

BigRed76 04-10-2012 01:55 AM
Re: '71 C10 Fast Idle Solenoid
 
Ok. I dont think its worth trying to make it work right, but thought maybe somebody would have some insight on it.

DT1 04-10-2012 10:09 AM
Re: '71 C10 Fast Idle Solenoid
 
I always thought it was an anti dieseling solenoid that completely closes the primary throttle plates when the engine is shut down.
I actually re-wired mine to the A/C switch so it will slightly bump the idle up only when the air is on.
Since you don't have A/C, it wouldn't hurt to remove it.

dznucks 04-10-2012 06:03 PM
Re: '71 C10 Fast Idle Solenoid
 
^^^ I agree. if you want to run it, set your idle speed with it hooked up.

The fast idle solenoid can be hooked up to increase rpm when a/c compressor is on or used for anti-dieseling

Autoblueprint 04-10-2012 07:29 PM
Re: '71 C10 Fast Idle Solenoid
 
Quote:
Originally Posted by BigRed76 (Post 5301835)
On the right side of this picture is what I know as a fast idle solenoid. I know that when its plugged in it works, but it never shuts off to allow normal idle. I also noticed that there are two vacuum ports on the side of it that are not connected. Does anyone know how these are supposed to operate? Or is it not worth my time to mess with it?
It is called a C.E.C. ( Combination Emission Control ) valve and a complete explaination ( three paragraphs ) of it's function can be found in Section 6T of the 1971 Factory Service Manual.

The lower vacuum port connects to manifold vacuum and the upper port connects to the vacuum advance on the distributor.

One of the electrical connections connects to the water temp. switch which is wired through a 15 second time delay relay and the other connection is wired to the transmission switch and is wired to a reversing relay.

According to the service manual if the C.E.C. does not function it will result in no vacuum advance and no high gear deceleration position of the carb.

Again I urge any one who owns one of these trucks to purchase the factory service manual...it is an invaluable tool to help one figure things out.

Sport/Truck 04-10-2012 10:56 PM
Re: '71 C10 Fast Idle Solenoid
 
Quote:
Originally Posted by Autoblueprint (Post 5305787)
It is called a C.E.C. ( Combination Emission Control ) valve and a complete explaination ( three paragraphs ) of it's function can be found in Section 6T of the 1971 Factory Service Manual.

The lower vacuum port connects to manifold vacuum and the upper port connects to the vacuum advance on the distributor.

One of the electrical connections connects to the water temp. switch which is wired through a 15 second time delay relay and the other connection is wired to the transmission switch and is wired to a reversing relay.

According to the service manual if the C.E.C. does not function it will result in no vacuum advance and no high gear deceleration position of the carb.

Again I urge any one who owns one of these trucks to purchase the factory service manual...it is an invaluable tool to help one figure things out.
I find it easier to just remove things I don't understand. :lol:

Indyuke 04-11-2012 09:46 AM
Re: '71 C10 Fast Idle Solenoid
 
lol

RexDodge 04-11-2012 09:56 AM
Re: '71 C10 Fast Idle Solenoid
 
Quote:
Originally Posted by Autoblueprint (Post 5305787)
It is called a C.E.C. ( Combination Emission Control ) valve and a complete explaination ( three paragraphs ) of it's function can be found in Section 6T of the 1971 Factory Service Manual.

The lower vacuum port connects to manifold vacuum and the upper port connects to the vacuum advance on the distributor.

One of the electrical connections connects to the water temp. switch which is wired through a 15 second time delay relay and the other connection is wired to the transmission switch and is wired to a reversing relay.

According to the service manual if the C.E.C. does not function it will result in no vacuum advance and no high gear deceleration position of the carb.

Again I urge any one who owns one of these trucks to purchase the factory service manual...it is an invaluable tool to help one figure things out.
Wow. Nice explanation and I second the manual advice. :agree:


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