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Danski · Posted: Sun Oct 26, 2014 8:58 pm Post subject: yaaaay cold start problems :-D

Okaaay so recently my car has run like a dog when cold starting. After 5 mins of driving shes all good though. I have read over the Haynes manual and will do the checks of the WUR, Aux air valve and cold start valve etc. But before I do just thought I'd describe the symptoms in case it could be something else entirely. Basically my car starts and runs rough and idles really low for 5 mins but after the engine has warmed up the car suddenly idles perfectly. I have checked the aux air valve and it is open when cold. Basically I think I know what to check but what would be the most likely culprit for the symptoms described above? I have heard that if it was the WUR then the engine would die when I rev it which is not the case, the engine actually runs better when I throttle from cold. I currently have the CO adjuster screwed out 2 turns as recomended on another post in this forum and I am happy with the mix and timing. Thanks again to anyone who posts a reply, this forum has seriously been invaluable to me as I am a newbie to fixing cars!
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1985 Porsche 924 NA

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Check WUR and AAV function per the manual. . .first steps.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

scriblz7 · Joined: 07 Dec 2008 Posts: 112 Location: kirkland WA.

definitely has something to do with the WUR and AAV
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Riley
79 924 n/a with gt body
15 VW GTI

Danski · Posted: Mon Oct 27, 2014 7:53 am Post subject:

Cheers guys, I'll give it a check today if it stops raining. Just hoping it isn't the thermo switch because that thing sucks to get to!
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1985 Porsche 924 NA

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

TTS would only effect initial startup, and would not effect cold mixture or idle speed.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Danski · Posted: Mon Oct 27, 2014 12:06 pm Post subject:

Well thats good news about the TTS. I checked the cold start valve this morning both with the plug out and with the plug in and the TTS bridged as per the Haynes instructions but I never saw any fuel come out of it. Not even a drop. There was fuel going to it as I slightly cracked open the line to it and could see/smell fuel. Is is possible that the cold start injector is fully stuck shut? Also the AAV is good as I tested it and it shuts properly/opens fully. Quite confused now!
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1985 Porsche 924 NA

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Possible CCV is not firing for sure, but remember pump must be running. Test with fuel pump relay jumpered, and if the results are the same take it to the injector shop for service.

Also, still need to check cold and warm control pressures and system pressure.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Danski · Posted: Mon Oct 27, 2014 2:19 pm Post subject:

arrrh just checked voltage to the CSV and there is no voltage being supplied regardless of if I jump the TTS or not. AAV is getting voltage though. Sorry for my ignorance but how do I jump the relay? Do I just bypass it behind the relay board.
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1985 Porsche 924 NA

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Also, it won't fire unless the key is in the start position.

Do a quick search for instructions to jumper the pump.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Danski · Posted: Tue Oct 28, 2014 7:27 am Post subject:

Soo from what I can work out, I put the jump wire in sockets 30 and 87 of the fuel pump relay, this should then bypass the relay so I can check that the relay is not the problem. I will then try to start the car and check the voltage across the CSV to see if any improvement. If this doesn't work can I just connect the CSV right up to the battery and try it that way?
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1985 Porsche 924 NA

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Pull the csv, crank it over and check for spray?

More likely WUR anyway.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

Danski · Posted: Tue Oct 28, 2014 12:31 pm Post subject:

yeh thats the plan Rasta Monsta! Hopefully its not the WUR!
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1985 Porsche 924 NA

jason c · Joined: 13 Jan 2014 Posts: 1018 Location: Nwi

Danski · Posted: Tue Oct 28, 2014 1:48 pm Post subject:

awesome!
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1985 Porsche 924 NA

Danski · Posted: Wed Oct 29, 2014 8:30 am Post subject:

ARRRG I think I have flooded the engine, not really sure how as I only jumped the relay for a very short time. Engine is definitely flooded though, stinks of fuel and the spark plugs are all wet. what do I do? I pulled out the injectors last night and gave them a soak in carby cleaner. I put them back in this morning to find the engine is still flooded, there was a minor explosion in the air box when I attempted to start it.
Not really sure what to do now, should I just pull the pump relay and spark plug and crank the engine over with no fuel/spark to clear it?
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1985 Porsche 924 NA