Topic: 71 TCS ... help !
in Forum: C3 Electrical
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I recently picked up a 71 Vette. It has 350 / 270hp, auto with A/C. I have put in a new wiring harness (engine, front end, and A/C) and I purchased the TCS harness as recommended by Lectric LTD. My issue is that I can't seem to figure out what this connects to. Is there supposed to be a sensor on the right side of the block ? A solenoid on the carb ? My car is apparently been stripped of these items and I need some instruction as to what components are involved and how to install & hook them up. I have looked at the wiring diagrams but this does not tell me what I need on the car to install the wiring. Any help would be greatly appreciated.
Thanks
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Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
Ronnie, can you give us some more detail ok your question? Lectric's wiring diagrams are usually a good reference once you get used to reading them.
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There should be a temp sending unit on the passenger side head, for the TCS system. I believe it is a three wire plug, but may be two wire.
Some engines were equipped with an optional block heater, which would go in one of the freeze-plug holes in the block, on the passenger side.
There would be a solenoid on the carb to raise the idle speed when the A/C is on...
hth
Some engines were equipped with an optional block heater, which would go in one of the freeze-plug holes in the block, on the passenger side.
There would be a solenoid on the carb to raise the idle speed when the A/C is on...
hth
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I KNOW, I KNOW!, Its for the vacuum advance selanoid which allowed vac. adv. in high gear only, which I don't really think you want, 
you would want advance in all the gears, 
the system included a delay relay, a temp sensor, a trans switch and a vac. adv. selanoid, put the tcs harness in the swap met bin, 
TCS= Timed Controled Spark anips 2009-08-06 13:18:49
you would want advance in all the gears, the system included a delay relay, a temp sensor, a trans switch and a vac. adv. selanoid, put the tcs harness in the swap met bin, TCS= Timed Controled Spark On my '71, which is an LS5 454 w/ mt and a/c, my Chassis Service manual describes the system as a "Combination Emission Control System", consisting of a CEC soleniod located on the carburetor to control vacuum advance to the distributor; a time delay relay, a reversing relay (both of these mounted on the firewall) ; a water temp. switch mounted on the passenger side head; a transmission switch (mounted on my manual trans.) and a resistor built into the wiring connecting these components. The description of the system is a little complex, but it's designed to control dieseling when the engine is turned off and stalling on pull away from a dead start. With cars with an a/t and a/c, there is a solid state time device to leave the a/c on for 3 sec. after you shut off the engine to bring it to a stop, thereby reducing dieseling.
I had replaced my wiring harness and the system didn't work until I determined that the time delay relay was bad. Once I replaced it, it seems to work as described in the manual. I had also ordered one of those TCS jumper wires when I bought the harness, but still don't know where it goes. ??
Dennis
how many wire's and what gage and color, I have a GM schemetic of the 71 tcs system, send me PM with an E-mail address and I'll send it to you if all else fails, did you call Lectric tech line and ask them, GM made changes to the TCS operating systems in 70,71,72-74, if your car is early or late 71, might be a system change overlap. anips 2009-08-09 20:44:29
in Forum: C3 Electrical
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