Engine Idle With Auto Trans Question
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Joined: May 2006
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From: Baytown Texas
Engine Idle With Auto Trans Question
This is the first auto transmission project I've had so I've never had to deal with it before. This is actually for my 70 Firebird, but I believe all GM's were set up the same as far as this goes. For idle control, the original had a TCS system that wired the transmission to the temp sensor and a vacuum sensor on the intake so that when it is put in gear, the idle would increase to compensate. How do you go around the TCS for idle compensation? There has to be a simple solution.
Thanks for any input.
Thanks for any input.
Thread Starter
Pro
Joined: May 2006
Posts: 576
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From: Baytown Texas
But where do you fnd it. I've looked at JEG's with no luck. I may not be looking in the right place though.
BTW- I have an Edelbrock carb.
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From: At my Bar drinking and wrenching in Lafayette Colorado
The purpose and function of the TCS is not to increase idle when you put it in gear. The system retarded timing at idle by eliminating vacuum to the vacuum advance control unit, thus reducing hydrocarbon emissions at idle. It only allowed vacuum advance when the engine was out of first gear. It was used in conjunction with a water temp switch, which could over-ride the TCS and put vacuum to the distributor (advancing timing) if water temp got too high (advancing timine reduces operating temp). There was never a system in use that increased idle speed in gear. The only system used was the A/C idle-up solenoid (also used as an anti-dieseling solenoid) which increased idle speed when the A/C was turned on (or which dropped idle speed when the engine was shut off, in the case of the anti-dieseling solenoid). There is no system for increasing idle speed in gear, as it is not needed.
Thread Starter
Pro
Joined: May 2006
Posts: 576
Likes: 1
From: Baytown Texas
The purpose and function of the TCS is not to increase idle when you put it in gear. The system retarded timing at idle by eliminating vacuum to the vacuum advance control unit, thus reducing hydrocarbon emissions at idle. It only allowed vacuum advance when the engine was out of first gear. It was used in conjunction with a water temp switch, which could over-ride the TCS and put vacuum to the distributor (advancing timing) if water temp got too high (advancing timine reduces operating temp). There was never a system in use that increased idle speed in gear. The only system used was the A/C idle-up solenoid (also used as an anti-dieseling solenoid) which increased idle speed when the A/C was turned on (or which dropped idle speed when the engine was shut off, in the case of the anti-dieseling solenoid). There is no system for increasing idle speed in gear, as it is not needed.
Thanks Lars, Your awsome!
