924Board.org

TheBib · Joined: 21 Aug 2011 Posts: 50 Location: Michigan

Moving onward to diagnosing my 1982 924 NA.

Tested the thermo time sensor like haynes says, at the cold start valve plug i inserted a test light, cranked the car, and the test light lit for 4-8 seconds the various times i tried it. did it with a volt meter, but was easier with the light.

I moved along to the cold start valve testing, and removed the plug from the Thermo time sensor per haynes and put a jumper between the two wires in the plug, removed the Cold start valve, cranked the car no spray. Guessing it is the cold start valve. I tested the cold start plug and from either terminal to ground got 12V while cranking the car.

So where do i get a new one, saw where parts Geek has one for about $300 bucks. Don't necessarly care about the money, althought i should, but just want the correct part.
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TheBib

Ozzie · Posted: Mon Sep 19, 2011 7:39 am Post subject: Re: Cold Start Valve, 1982 924 NA

Paul · Posted: Mon Sep 19, 2011 8:22 am Post subject:

Always use a 12V test light when testing a circuit, not a Volt/ohm meter, since you want to put a load on it.

Use your meter to check for resistance between the poles of the cold start valve.

These seem to last forever, so one of us can provide a working used one.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

TheBib · Joined: 21 Aug 2011 Posts: 50 Location: Michigan

ok, learn from the masters.

The cold start valve is fine. I didn't read this in time, but what i did was to go out and confirm my tests with the volt meter and using a jumper on the TTS. And yes same as before. Even removed the relay and jumpered the fuel pump relay with no luck.

so just hooked up the TTS and the cold start valve and cranked the car. well the cold start sprayed in a beautiful conical pattern for a 4 seconds or so. So basically elimated another check and learned in the process-use a test lamp.

thanks guys
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TheBib

Paul · Posted: Mon Sep 19, 2011 8:38 am Post subject:

The usual problem with the cold start valve is that it drips fuel when its not operatiing thus messing up the fuel mixture.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

TheBib · Joined: 21 Aug 2011 Posts: 50 Location: Michigan

i have performed that test and know it does not drip fuel. Although i am still left with the Haynes test procedure.

My TTS has a plug with two wires (green/white and red/white). When i jumpered these and cranked the car the valve did not spray. When i hooked back up the TTS and cranked the car the cold start valve functioned as it should.

Now maybe I should not be jumpering the two wires on the plug. Maybe i should be jumpering one to ground? I cannot actually see down there but there is another wire down there seperate from the plug on a spade connector like a ground, not sure.

In any case it works when the parts are connected, so for now, maybe i just don't understand the jumper test.
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TheBib

Ozzie · Posted: Mon Sep 19, 2011 8:38 pm Post subject:

yep- red n white to ground would have got it to spray.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

TheBib · Joined: 21 Aug 2011 Posts: 50 Location: Michigan

thanks Ozzie, that eases my mind. I have a lot of Haynes manuals over the years due to having a lot of cars over the years > 10 and by far the Porsche haynes manual is the most unclear.
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TheBib