QuestionQUESTION: Car cuts off after approx 20 min., won't re-start untill cool. Replaced relay, no fix. ECU?? If so, where is a respectable dealer I can buy a new ECU from or get mine repaired? Thank you.
ANSWER: Steve,
There are several things that can cause this. You need to check to see if the fuel pump is working and not getting hot. Get the fuel pressure checked when the car dies. If you have sufficient pressure then it is electrical. There is a transistorized ignition module by the coil that can cuase the problem too. Now, you did not say if the car will crank or not. If the car dies does it turn over? If yes, then the two items I have mentioned are probably of concern. If the car does not crank then the relay or the starter. Also, check the clutch switch if a manual or the neutral safety switch if an automatic. Lastly, if the oil pressure switch is defective it will kill the fuel pump relay. Email me if you need more.
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QUESTION: The car will crank after it cuts off, but the fuel pump is not getting the signal to pump fuel. When it is cold and turn the key, you can hear the pump energize. After it cuts off, the pump is not energizing, the starter does crank the engine, but no ignition due to no fuel.
Thanks again for the help,
Steve
AnswerSteve,
The ECM is cutting the power to the pump if the relay is not defective. That is, replace the fuel pump relay first. If that does not do the trick replace the oil pressure switch. Nissan uses the oil pressure switch as their fuel safety switch. Note, if you got into a wreck and the engine was killed there would be no oil pressure. No oil pressure and the pump turns off. You would not want fuel pumping out at an accident so that is why the oil pressure switch...
