I have a 2006 Nissan Altima 2.5 4 cylinder. It was not starting and I replaced the ignition coil packs, spark plugs, crankshaft position sensor and it did not start. I replaced the camshaft position sensor with a used one and it started after a bit of turning over. Then it started getting hard to start. I replace the camshaft position sensor with a new one and it turns over and attempts to start but acts like it is firing out of time. The scanner only gives me a random cylinder misfire code. Does anyone have any advice? Thanks much!
Start with the basics,do a compression test first. and post the numbers. Lots of things can cause misfires besides the ignition system. Low compression, bad valves, bad fuel injectors.
If you don’t know how to test for these, Take it to someone who does.
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The camshaft postion sensor replacement made it run which eliminates compression and fuel issues.
Which one is it ?
Attempts to start
Or
Runs
You are not living up to your forum name at all. The car didn’t start so you replaced all the ignition parts based on a P0300 code. That didn’t work nor did the cam sensor, for long. You jumped to the answer without doing a proper diagnosis.
Humor @oldtimer-11 and run a compression test. Then check the fuel pressure. Then check for spark. All 3 are needed to make the car run. If you don’t have spark, you know all the parts are new, the command to spark is the issue. If you have spark and compression but it won’t start, spray starter fluid into the intake. If it starts and runs for a moment, you have a fuel problem. If the fuel pressure is OK then there is likely a fuel injector problem. Check the signals with a noid light.
If you get this far, post back with what you find.
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No. It “attempts to start but acts like it is firing out of time.”
Check for a defective VVT solenoid.
Tester
I’m guessing the cam sensor involvement is a red herring. On most engine designs the engine will still run ok even if the cam sensor completely fails. The computer works around that problem by firing the plugs on both compression and exhaust strokes is all. This can cause the coils to overheat if the engine is run at high speed for a long time, but it still takes quite some time before they fail from overheating. Suggest next time it cranks but won’t start, do the tests required to determine if the problem is fuel or spark. For example if you spray starter fluid in the air intake and it starts right up, you know it’s likely a fuel problem. Could be something more complicated of course, but that’s where I’d start.