replacing cold start valve 80sc

[paj]

Has anyone ever replace the cold air start valve without removing the engine? I can feel it, but it doesn't look easy to do. I just got this running this winter and now that it has warm up in the Midwest it doesn't want to start after driving it for a half hour or so. I can push the pedal down and it will start after third or forth time. so I'm thinking it must be the valve? This is my first Porsche so I'm behind on the knowledge. thanks pat

[psalt]

Pat,

Try searching for "warm start problem", it is usually a residual pressure issue (check valve) and you need a CIS pressure gauge to test for it. The cold start valve sprays fuel only when cranking and only when cold. The ground connection is controlled by a switch on the left timing chain case and is easy to test. Do not pump the pedal when starting, you are asking for a blown airbox. The CIS lambda system on you car does not respond well to blind part swapping, but it will tell you what is wrong if you have a dwell meter, a voltmeter and a pressure gauge.

[Scott R]

I'm not saying the valve is bad, they seldom seem to go out. But if you do need to replace it, it can be done in-situ.

Remove the air box cover
Remove the rubber air boot
Remove the throttle body
Unplug the CS valve electrical connector
Disconnect the fuel line to the back of the CSV (take not of the crush washers here)
Remove the two (I believe 6m) allen screws
Remove valve.


And in true "Haynes" fashion "assembly is the reverse"

But really check what was posted above first, they don't go bad very often.

[KNS]

+ what the other guys said. If the car has been run for just a few minutes from cold, the next start should fire right up (and the CSV would not function at that time). You can get to it, I watched a Porsche mechanic reach around the back side and remove it. A partial engine drop would help.