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Really appreciate everyone's help on the last issue I posted!

The last couple of days my 83 320i has not started periodically. I have to let the car sit for about an hour and then it usually fires up. It runs rough for a couple of minutes and then settles into a decent idle.

It is extremely cold here right now which I'm guessing is a factor in this situation. I plan on pushing the car into a heated garage to let it thaw overnight.

Any guesses on what might be causing this? Vapor lock? A fuel pump on its way out?

Any direction folks can point me in for troubleshooting would be appreciated!

Search function does wonders
http://www.bmwe21.net/forum/viewtopic.p ... 6&p=213745

Bad CSV would be my guess

The cold start valve (CSV) mentioned is an extra fuel injector that supplies additional fuel to make cold starts easier. With your engine I believe it is mounted in the intake manifold just above the valve cover.

The CSV is electronically operated by a thermal switch (thermo time switch or TTS, located at the top front of the engine) so the first thing you can do is to check if it is being operated at all. With cold engine, measure on the connector if its being switched on at all. If no power, the thermo time switch or wiring is under suspicion (including fuse that may be corroded, believe that's fuse no 3).

If you do have power, the injector could be stuck. Before removing it from the intake manifold make sure you have a new gasket/o-ring on hand otherwise you will have a dangerous leak after refitting. Remove the injector, leave the wiring on and be careful with the brittle fuel line. Carefully place the injector in a jar and start the engine and see if it actually is injecting fuel.