QuestionQUESTION: Calvin, I have a 1995 Nissan 3.0L 4x4 pickup. The engine runs great when cold, but when the engine heats up, I will get a loss of power. The hotter it gets, the worse it gets. If I drive it for 10-15mins, shut it off and wait 10-15mins, then restart, I notice an extreme loss of power. At that point, it will not get above 15 mph. I would think that is when it is at its hottest.
I connected a timing light to the coil wire and noticed loss of light every time I have loss of power (as I rev the engine). So it appears I have isolated the problem to the ignition. I have replaced the plugs, wires, distributor cap and rotor, coil, and power transistor.
I feel that I am running out of items to check.....bad ground to the ECU? MAFS? Battery (it is 7 or 8 years old)?
ANSWER: Hi Steve -
You have done everything I would have done. Only other thing I can think of is the ignition module, located in the distributor. They have been known to fail when the engine gets hot.
Pehaps that could be the culprit.
Let me know -
aloha
calvin
---------- FOLLOW-UP ----------
QUESTION: Calvin, what you referred to as the ignition module, I referred to as the
power transistor. Not sure where else to go with this. I know the mafs
measures air flow based on change in temperature through the intake.
Could this be sending bad info to the ecu?
AnswerOK, Steve -
Got it. That MAF sensor can be cleaned, however there is a special cleaner. Do not use carb cleaner.
I can't think of anything else, could be battery if it is that old, but doubt it. ECU, also a possibility, I assume you are not getting a check engine light on?
calvin
