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My warm-blooded car...

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Dear Tom and Ray:


I recently bought a 1985 Nissan 300ZX. The used-car dealer told me it had just been tuned up, but it runs roughly and makes white smoke first thing in the morning. After about 3 or 4 minutes, it runs great. Is this car just warm-blooded or does it have a problem?
Rhonda

RAY: There may be something wrong with the "cold start" mechanism. My brother has that problem. The colder it is, the longer it takes him to get started in the morning. When the temperature falls below say, 65, he doesn't get to work until noon!

TOM Actually, the cold start mechanism is the equivalent of a choke on fuel injected cars. If it were malfunctioning, it could cause the car to run rough for the first few minutes.

RAY: The more serious, more costly, and more likely possibility is that these are the early symptoms of a blown head gasket or warped head. If the head gasket were starting to come apart, a little bit of coolant could leak into one of the cylinders, and cause the car to run on five cylinders until the engine warmed up. Once the engine warmed up, the gasket would expand and reseal the leak until the next time you shut off the car.

RAY: Have a Nissan dealer test the head gaskets. If that's the problem, it's going to cost you big bucks! And unless you got a warranty on this car, not even the Beach Boys will be able to help you Rhonda.
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