TCS/ABS tach mystery

[BATMANs]

Car is fixed. Extended alternator wire left over from CTSC install got stuck under the intake manifold, wore out, and started shorting under heavy vibration.

Im having the same problem too.

I'll check this out.

 

[angus]

Also, I recently had a car with a failing ignition switch - when it first began it had the same symptoms - it took months for it to get to the point where the car would not stay running.

 

[BATMANs]

The other thing that I noticed that happened around the same time is that sometimes my A/C doesn't blow cold air (I can be running it for 30 minutes just to give more than enough time for the temp sensor to figure it out and to purge out the warm air).... and then all of the sudden it works.

I checked all of the wiring around the alternator and it seems fine.

Where else should I look?

When my car is running there is this momentary "hiccup" where the car hesitates and the tach is "forced down" to zero even while I'm in gear. The tach doesn't just drop. It's forced down and pops back up as if everything is OK.