Another TCS technical question!

[Rick Church]

You guys have really educated me in the past few days about this 1971 TCS system and I appreciate it. I have a few questions though. On my car, the TCS solenoid is functional. A previous owner removed the wire going to the RH head temperature switch and then (I believe) screwed in the plunger on the TCS solenoid to keep it from interfering with the cars idle speed. However, when the key is turned to the ignition position, the TCS plunger extends as it should but does not retract (on warm up) as the temperature switch never signals the TCS solenoid to retract. Here are my questions: If the plunger remains extended and the vacuum to the distributor is set to a given value, does this interfer with the normal operation of the car? Would this affect gas mileage and performance? Until I get it the system straightened out, should I run the vacumm hose directly from the carb to the distributor advance? Sorry about all the questions.

Sincerely,
Rick Church

[Dave S.]

Re: Another TCS technical question!

Rick,
I would think you may have a defective 444 switch or the time delay relay may be fried in addition to the possibility of the head sensor issue. I don't have the time delay relay number in my head but it is either 842 or 843.

[Jack H.]

Correct term is CEC, not TCS....

The 'malady' you describe (CEC solenoid plunger always extended) suggests there are other problem issues. The temp switch that's not connected (RH cylinder head) was a single pole, double throw, unit. Made contact to ground with engine cold, went to open circuit with engine at 'normal' temps, and went to ground with engine entering overheat. So, for your solenoid to be always activated, it's 'seeing' a need for CEC engagement from one or more sources.

If the temp switch wiring harness that was removed is somehow permanently grounded, this is exactly what will happen. If the system's time delay relay is 'fried' refusing to open and self-latch open, this is what will happen. If the transmision switch is blown (permanently closed) this is what will happen. If the lead wire to the transmission switch was improperly routed (not through the associated underbody clips) and it's 'fried' to the exhaust pipe and/or its insulation was damaged and it's making contact with the trans case, this is what will happen.

Absent any of those maladies, I'd suggest your CEC reversing relay is over the hill. Good luck!