Questions and Answers

Mazda MPV Hard Cold Weather Starts Q. Hi, I hope you can help me. My girlfriend has a 1991 Mazda MPV, V-6, 2WD with 130,000. In the past month the battery, alternator, distributor, cap, rotor, plugs and wires, intermediate exhaust pipe, muffler, and tail pipe were replaced. Since then, the temperature in Michigan has dropped outside, and her vehicle cranks and runs for a few seconds in the morning and dies.

If you leave the key in the ignition in the on position, it will usually start within 5 to 15 minutes, approximately 5 to 10 cranks. I've had the fuel pump tested and everything checked out fine. It's been to the mechanic several times and they cannot find anything.

If the vehicle sits for more than a few hours and the outside air temperature is below 50°, the problem begins. Is this a fuel injector problem, electrical, or is there a cold temperature sensor that I can replace? Any ideas/help would be greatly appreciated.

A. There is a Coolant Temperature Sensor (CTS) that tells the PCM what the engine temperature is. If it is reading hotter than the actual temperature, the PCM will provide the wrong air/fuel mixture for a cold start.

The CTS is screwed into the thermostat housing near the top radiator hose.