How do I check my cold start and....

DMX · 05-05-2003, 07:14 AM

How do I check If my cold start and thermo switch are working....

They have been disconnected ever since I bought my car and I

am connecting them tonight... How do I check if these things are

getting power or are working.... Is there any special way...?

Thanks.

derek murray · derek murray's Garage

What year is your car?

DMX · 05-05-2003, 09:55 AM

'75 911....

azasadny · azasadny's Garage

DMX,

Did anyone answer you? I have a 1974 wirth CIS and have the exact same questions. The rear electrical tray has a bunch of loose wires and the cold start relay was missing. I need to understand where the wires are supposed to connect to fix the PO's "fix"!!! Thanks!

azasadny · azasadny's Garage

Many of you have followed my intermittent "cold starting" problem that eventually became a constant starting problem that caused my to have to crank my car 20-30 times, with several loud backfires, prior to the car starting. Once the car started, it ran great but the starting problem was driving me nuts. Needless to say, I replaced alot of components (fuel filter and accumulator, cold start valve and thermotime switch, throttle microswitch, plugs, CD unit, rotor, coil, Pertronix unit, WUR, etc...

Each replaced item improved the situation temporarily, but the problem still persisted. The cold and warm pressures were within acceptable limits and I had good spark at plug #1, but the car just cranked and refused to start. To make a long story short, this is what the mechanic found:

- The plugs were improperly gapped (too wide) even though I followed the instructions on the PermaTune CD unit for spark plug gapping specs.

- The plug wires and their "boots" are bad and I will replace them

- The "new" throttle microswitch that Jordi Riera sent to me worked perfectly and the old one was bad

- One of the wires coming off the Pertronix unit had rubbed until the insulation was off and bare wire was showing.

My mechanic "fixed" these things and the car starts on the first crank, idles at 950rpm and runs great. I REALLY appreciate all of the assistance so many of you have provided. I have learned alot from you kind folks. I'll post this update on the other posts that I have been on so that anyone with a similar problem may be helped. I had checked the spark at plug #1 and had a nice spark, but my mechanic showed me that others were weak. I hope this helps others out there....