Questions and Answers

Volkswagen Jetta No Start When Cold Q. Hi, I have a 1996 Volkswagen Jetta 2.0 liter, automatic transmission with 180,000 miles. It cranks but does not start in cold weather. Also, it sometimes misfires and hesitates on the highway when accelerating. I had my local mechanic look at it and he thinks it may be a compression issue? Any information is appreciated. Thanks, Frank

A. There are a number of things that can cause the symptoms you describe. Too many to go into here. If your mechanic believes it's a compression problem, he should do a wet and dry compression test. I would suggest an oil and filter change first in case there is fuel in the oil.

Good compression should be 7.0 bar or higher with no more than a 3 bar difference between cylinders.

If the compression checks out good, we need to know what's missing when it won't start, fuel or spark. When it won't start, squirt a good shot of carburetor cleaner into the intake manifold through a vacuum line. Then try to start it. If it starts and runs as long as the carburetor cleaner lasts, you have a fuel problem. If not, then it's an ignition problem.

I would also check the Engine Coolant Temperature sensor. A bad sensor will lean out a cold fuel mixture and prevent starting.