# Crankshaft position sensor 04 Maxima



## edortir6 (May 26, 2006)

What are the symptoms of a bad crankshaft position sensor?


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## smj999smj (Jan 1, 2006)

Misfiring, stalling, and/or no start, no spark.


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## edortir6 (May 26, 2006)

All at the same time? What i have is a consistant misfire.


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## 05SmokeSE (Mar 23, 2011)

edortir6 said:


> All at the same time? What i have is a consistant misfire.


The crankshaft position sensor (CPS) sends a signal to the PCM (powertrain control module) that the PCM uses to know when to fire the spark plugs. If your CPS is going bad it will affect ALL plugs and, when the CPS fails completely, the engine just shuts off like you reached over and turned off the key.

The circuitry in the CPS is adversely affected by heat, which is what causes them to fail eventually. The problem is that they can take a while to fail completely, in the meantime they give you this engine runs, engine doesn't run, engine runs after it cools down for ten minutes, symptom. Once it completely fails, you're done and the engine will not start again until it's replaced.

If you have a consistant misfire, you probably have one or more bad coil-on-plug assemblies. Each spark plug has its own ignition coil attached directly to it. If that individual plug's coil is bad, that plug will not fire or not fire consistantly.

Does the engine misfire just sitting and idling in park? If it does, just start pulling the connectors off of the coil-on-plug assemblies one at a time until you pull one that stops the misfiring. Then, that's the bad one. Replace it.

Of course, you have to remove the fancy big plastic shroud from the top of your engine so you can get at them.

Good luck with it.


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## smj999smj (Jan 1, 2006)

I would have it checked for codes prior to attempting to pinpoint a failed coil by disconnecting the harnesses. It may save you a lot of work by giving you a code that pinpoints which cylinder is misfiring.


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## edortir6 (May 26, 2006)

I got the codes from the car several times ond it's always cylinder 3 misfire. I don't think it's the coils, plugs, or sensors. I changed the plugs and the coil pack for #3 already. I changed both cam sensors and crank sensor. The only sensor that has not been changed is the throttle position sensor. I also checked the compression on all cylinders and replaced the ECU. I'm 2k into this problem and ready to sell it. It's so frustrating and I hate to sell it because it's a beautiful car, but it's been a money pit.


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## 05SmokeSE (Mar 23, 2011)

edortir6 said:


> I changed the plugs and the coil pack for #3 already.


Trust the error codes, and only look for problems with #3 cylinder. Don't mess with anything that affects ALL cylinders like the other sensors you mentioned.

If you have already replaced the #3 plug and coil pack, then it has to be either the wires or the connector that connect to the #3 coil-on-plug assembly. If either the wire or the connector is bad, #3 cylinder won't fire even if the PCM is telling it to.

Pull the connector off of the coil pack and then check the wire and connector for continuity with an Ohm meter. I'm not sure off hand exactly how far back you can trace that wire from the coil, but you need to trace it back as far as you can. On the other hand, my bet would be that it's not the wire way back in the wire bundle somewhere, but rather a bad connection of the wire right at the connector on the coil.

Back probe the wires a few inches back from the connector with one lead of the Ohm meter and connect the other Ohm meter lead to the terminal in the connector that wire connects to. There should be little or no resistance. Do each wire/terminal separately. If there is any resistance in either, that's your problem.

You can also do a "wiggle test" on the wire/connector while you are taking your resistance check with the Ohm meter. If the resistance reading changes while you are wiggling the connector, there's your problem.


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## edortir6 (May 26, 2006)

That car is not my problem anymore. I wrestled with it long enough so i sold it.


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## smj999smj (Jan 1, 2006)

Well, that's one way to fix it! ;-)


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## Eric fowler (Aug 20, 2014)

*Camshaft issue*

I have a 04 Nissan maxims and its have a camshaft sensor problem in bank 1 code p0240. I changed it useing a after market part sensor. It drove ok then about a hour into the drive i started have the same issue again and the same code came back again. It's the only code that comes up. Do you think I need to change both camshaft sensors & the crank as well?


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## smj999smj (Jan 1, 2006)

I wouldn't trust the aftermarket sensor; I've seen to many of them bad out of the box or fail shortly after. I only use genuine Nissan cam and crank sensors for that reason.


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## rogoman (Dec 16, 2004)

Eric fowler said:


> I have a 04 Nissan maxims and its have a camshaft sensor problem in bank 1 code p0240. I changed it useing a after market part sensor. It drove ok then about a hour into the drive i started have the same issue again and the same code came back again. It's the only code that comes up. Do you think I need to change both camshaft sensors & the crank as well?


It's recommended by many mechanics to always replace both sensors. Nissan used to sell a kit that included both sensors; don't know if they still do. Like SMJ said, use only OEM sensors.


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