relays on the firewall?

[joe69rs]

Hey Guys,

 

There are two relays mounted to the firewall on the passenger side of the distributor of my 71 Monte. What do these relay's control?

 

Any help would be appreciated,

 

Thanks,

Joe

 

btw, this car has air conditioning.....

[Sam (Bones)]

one is the hi-speed relay for the blower motor, the other I THINK!! is for the idle kicker when the A/C is turned on

[joe69rs]

the hi-speed fan relay is mounted in top of my heater box with an inline fuse going to it.....

 

i have to run out for a minute (into the cold...brrrr) and i'll try to snap a picture.

[monte70car]

one is probably the trans sprak control

[joe69rs]

here's a pic of the relays i'm talking about (circled).....u can see the hi-speed fan relay on the left.

 

[DavidTX]

The 71 does not have an "idle kicker". The relay on the carb is activated anytime the ignition switch is on. It is to prevent the engine from dieseling. It allows the carb butterflies to close completely to prevent fuel from entering the intake manifold.

I had my 71 over a year before I found out about that.

[MagicDragon42]

The two relays are an early attempt to meet emission standards by disabling the vacuum advance to the distributor unless the transmission was in high gear and the temperature was above a certain level. It is called TCS or Transmission Controlled Spark. One is a relay and the other is a time-delay relay. The TCS solenoid on the carb was activated to block the vacuum advance. Here is a wiring diagram = http://i291.photobucket.com/albums/ll306/MagicDragon42/TCS001.gif

 

Here is '71 A Body wiring diagram with TCS relays on right side, center.

http://i291.photobucket.com/albums/ll306/MagicDragon42/MCWiring12-5.jpg

 

If you have factory air, there is another time-delay relay under the dash on the passenger side that activates the air conditioning compresser clutch for 5 seconds after the ingition switch is turned off to prevent hot engine "run-on" or dieseling.

 

I replaced my stock Quadrajet carb with a Holley and removed all of the TCS relays, wiring, and solenoid and do not have any problem passing Colorado emission tests.

 

Mike