flatsixcrazy

Hi Everyone,
My 964 just went kaput yesterday by refused to idle, hunts for idle speed and then cuts out. My hammer indicated that the "idle contact" is at fault and "open circuit presence". Can someone please help me with a part number for the idle contact switch and a good source in the left coast?. Thanks for all your help. Andy

dfinnegan

I think it's part 21 in the attached. Someone please chime in if I have it wrong.

Try Sunset Imports

flatsixcrazy

Thanks for the part number. Sunset Porsche quoted $164.50 (911 606 019 00)for the switch. I am going to try and clean the microswitch up this weekend. If it doesn't do it, I'll have to order one. Thanks again. Andy

Richard Curtis

Andy: please let us know if cleaning the microswitch fixes the problem.

Wachuko

Is this a situation where you would try to clean the contacts first and then try a new DME Relay as a second option to cure the problem?

Just trying to find out since without the reading from the hammer my first choice would have been to replace the DME Relay...

dbf73

I just found the one I bought several years ago and posted it for sale this morning

JasonAndreas

The microswitches are hermetically sealed so basically you can clean the pin contacts on the wiring harness and that is about it. A replacement idle switch comes with a wiring harness but for $164 I would try buying the switch direct, they are made by Cherry and are model DC9. The fanbelt warning switch is a DC3.

The DME relay has no connection with the idle contact switch, so no.

flatsixcrazy

Un-freakin-believable!!!!!. So I cleaned the electrical contacts of the idle microswitch and still had the same problem. I then changed out the battery because I have not driven the 964 in 4 weeks and the old one has been flat a few times already. It started up good but idling rough with intermittant drops in RPM and poor throttle response, similar to when I had problems with the coils a few months ealier. So I hook up the hammer to test the idle microswitch and it shows that the idle microswitch does open and close as it should when I press in and release the gas pedal and is no longer a fault. I then went back and check for fault with the DME and 2 faults registered. 1) Hall sensor and 2) knock sensor. Are the two sensors interrelated in someway?. What may have cause both sensor to go out at the same time?. Andy

dfinnegan

Have you checked for sparks in the dark?
Could be your wires shorting.

911URGE

My C4 developed this issue almost overnight. I cleaned the Idle Control Valve and the Air Flow Meter with throttle body cleaner (Carb cleaner) and was amazed at the improvement. Idles better, smoother and better response. In fact it idles at the correct 840 +/- 40 rpm where before it was idling around 600-650 rpm. I also discovered arcing at the plug wire boots on the distibutor cap. I applied some dielectric silicone to the boots and wrapped with electrical tape and have reduced the arcing to almost nothing until I get new plug wires, caps and rotors.

I do not own a Hammer but Ive read somewhere that you have to be careful interpreting the results the Hammer is displaying. If the car is idling poorly could the error from the Hall & knock sensors be a result of the poor idle and not the cause???

flatsixcrazy

Yup,
The coil to distributor wire shorted and sparks on one of the coil. Lesson learned, in order to get the correct reading form the hammer, the base line performance has to be in order. Otherwise you'll only get false reading. Thanks again for all your help.

H964

i do have the switch(964 606 019 00) . its brand new 65$ shipped. i bought from sunset porsche few months ago. pm me if interested