Whats this vacuum switch do?

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pacman1318

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On my 84 K10 I have it has a vacuum switch on the passenger side firewall that looks like the tc lock up thats on the driver side.
When I got the truck I was surprized it would even start or move after I saw what was unplugged under the hood. the switch has a 2 pin plug in and should have a vacuum line. Just wondering if it has anything to do with the ac or heat controls because it just blows out on the floor with no defrost and I have tried plugging in the couple of loose plugs haging down on the firewall and really dont notice anything is different.
I am trying to remove any unwanted items since we dont have smog trolls here in Bama.
P.S. I have removed the cruise control wiring harness if anyone wants it.
Thanks ahead for any info and I did search the forum for the answer before I posted so I am sorry if I missed it.
84 K10 305 700 r4 power windows and door locks a/c and did have cruise.
 

VAL

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That's the "Tip In" vacuum switch, used with ESC, for distributor vacuum.
 

chengny

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This regarding ESC as used with an HEI system:

Some models are equipped with and Electronic Spark Control (ESC) system that controls spark timing in order to provide maximum engine performance while preventing detonation. The ESC system consists of an engine mounted knock sensor and an electronic controller, Fig. 3. ESC is a closed loop system that monitors engine detonation through a sensor and constantly adjusts ignition timing to provide the maximum usable spark advance while preventing prolonged detonation.
The ESC knock sensor monitors the presence and intensity of engine detonation by sensing the resultant vibrations. The sensor produces a voltage signal which is proportional to the intensity of the detonation and this voltage signal is transmitted to the controller. The ESC controller is a hard wired signal processor/amplifier that operates in the 6-16 volt range, and has no memory storage provisions. The controller monitors knock sensor voltage output, processes these signals and controls the amount of spark advance through a special circuit in the HEI ignition module.

In addition, models with automatic transmissions include an ESC vacuum switch. The vacuum switch provides a signal to the ESC controller during throttle tip-in which causes the module to momentarily retard spark timing to prevent detonation on acceleration.

So:

1. It has nothing to do with your HVAC system

2. You could remove it if you wanted to. But if the other ESC components are still installed and functional, you might consider hooking everything back up. Performance may improve by re-activating the system.
 

pacman1318

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This regarding ESC as used with an HEI system:

Some models are equipped with and Electronic Spark Control (ESC) system that controls spark timing in order to provide maximum engine performance while preventing detonation. The ESC system consists of an engine mounted knock sensor and an electronic controller, Fig. 3. ESC is a closed loop system that monitors engine detonation through a sensor and constantly adjusts ignition timing to provide the maximum usable spark advance while preventing prolonged detonation.
The ESC knock sensor monitors the presence and intensity of engine detonation by sensing the resultant vibrations. The sensor produces a voltage signal which is proportional to the intensity of the detonation and this voltage signal is transmitted to the controller. The ESC controller is a hard wired signal processor/amplifier that operates in the 6-16 volt range, and has no memory storage provisions. The controller monitors knock sensor voltage output, processes these signals and controls the amount of spark advance through a special circuit in the HEI ignition module.

In addition, models with automatic transmissions include an ESC vacuum switch. The vacuum switch provides a signal to the ESC controller during throttle tip-in which causes the module to momentarily retard spark timing to prevent detonation on acceleration.

So:

1. It has nothing to do with your HVAC system

2. You could remove it if you wanted to. But if the other ESC components are still installed and functional, you might consider hooking everything back up. Performance may improve by re-activating the system.
Thanks for the info, I don't think there is anything other than temp and pressure sensors left on the motor.
On the driver side there is a oil pressure sensor down by the filter and a small can beside the distributer I think is for the oil pressure gauge, a sensor in the head water jacket by #1 plug and another one down by the starter I thought was for the temp gauge.
Can I put a volt meter on the wire going to the distributer to make sure its getting 12V or is there another way of testing it to see if it is active?
I should have been born earlier in life, I am trying to build a truck that is simple.
I have a jeep that the service man fix's with a laptop and one is enough.
 

pacman1318

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What I thought was the temp gauge down by the starter is the knock sensor?
 

350runner

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This regarding ESC as used with an HEI system:

Some models are equipped with and Electronic Spark Control (ESC) system that controls spark timing in order to provide maximum engine performance while preventing detonation. The ESC system consists of an engine mounted knock sensor and an electronic controller, Fig. 3. ESC is a closed loop system that monitors engine detonation through a sensor and constantly adjusts ignition timing to provide the maximum usable spark advance while preventing prolonged detonation.
The ESC knock sensor monitors the presence and intensity of engine detonation by sensing the resultant vibrations. The sensor produces a voltage signal which is proportional to the intensity of the detonation and this voltage signal is transmitted to the controller. The ESC controller is a hard wired signal processor/amplifier that operates in the 6-16 volt range, and has no memory storage provisions. The controller monitors knock sensor voltage output, processes these signals and controls the amount of spark advance through a special circuit in the HEI ignition module.

In addition, models with automatic transmissions include an ESC vacuum switch. The vacuum switch provides a signal to the ESC controller during throttle tip-in which causes the module to momentarily retard spark timing to prevent detonation on acceleration.

So:

1. It has nothing to do with your HVAC system

2. You could remove it if you wanted to. But if the other ESC components are still installed and functional, you might consider hooking everything back up. Performance may improve by re-activating the system.
This dude rocks...

Sent from the dust in front of you!
 

Hoodbj

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pacman1318

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Thanks guys, I'm installing a new motor (thats another story in the forum) I'm going to try leaving it off and doing any knock control with the distributer.
 

chengny

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If you are installing a new power plant, just use a non-ECS distributor.

You can then strip the associated wiring/TIP switch/hose - and remove the module from under the dash. Obviously, no knock sensor will be needed on the new engine.

The distributor will then only require one external lead - ignition switched 12 VDC to the coil primary (supplied on the pink wire).
 

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