I am working on my neighbors 2000 Altima 2.4 auto with 150k miles. In the midst of a confusing night he accidently installed a new battery backwards (neg on pos- pos on neg). As a result, the starter turns but the engine won't start. Realizing that there was no spark at plug level he replaced the plugs, plug wires, distributor cap, and rotor button. He found a blown fuse for the security system and replaced it.
I have had some trouble finding accurate diagnostic info because his ignition system is different than most of the ones I can find on the net. All of the ignition components, such as the coil and cam sensor, are located inside of the distributor. I have tested everything in the distibutor for resistance, power, and ground as per the Haynes manual and all test good. I have also tested the igntion resistor, and checked all fuses and links which all check good. I have also checked for fuel rail pressure which is within spec. The code scanner seems to be communicating with the ECM and returns no codes or errors which seems to rule out the cam or crank sensors.
On two seperate occasions over the last 3 days, the engine did fire, once there was a very weak spark at plug level, and another time the engine actually started and ran fine for about 5 minutes and the shut off and would not restart.
If anyone knows any other tests that I can run on the ignition system or ECM please let me know. I really don't want to start throwing parts at it especially considering the price of the distributor.
Thanks in advance.....