Questions and Answers

Jeep Cherokee Hates Cold Weather Q. Good Afternoon: My 1992 4.0 liter MPI 4x4, automatic transmission, A/C and 104,000 miles. Does not like to start below 40°. When I turn on the key it will take up to 90 seconds before I hear the fuel pump and the vacuum motor slowly kick in. Then when I crank, it will start and stall two or three times then run.

I put in an ignition switch, fuel pump, pressure regulator, idle motor, coolant and manifold temperature sensors and MAP sensor. Any suggestions?

Thanks,
Mike

A. This is going to take some work to locate the problem. First thing I would do is check all the terminals in all the harness connectors. They expand and contract with temperature and it is possible a lose one will lose contact cold and resume contact when it warms up.

It's also possible the PCM got temperature sensitive. On a warm day take it out and put it in the freezer for a few hours. Then quickly re-install it and try to start the car. If it shows the same symptoms, you have a bad PCM.

You can do similar testing with other components as well. I usually use a little freon to chill parts. I would start with the ASD relay and that area first. I think that is the most likely place for the problem to be.