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Discussion Starter · #1 ·
2002 Altima 3.5 car runs amazing until it warms up then it will randomly shut off but won’t start until for atleast 30min later…I have changed maf sensor, both cam sensors, crank sensor, temp sensors and vias sensor. Also it’s not throwing a check engine light or nothing. I’m at a dead end road…if some one could steer me in the right direction it would be greatly appreciated. Also has new battery and connections are clean
 

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Check your fuel trims and see if maybe it's running lean. If so, try running some SeaFoam or Gumout through it and try cleaning your throttle body. The biggest change between cold and warm is that fuel system goes from "open loop" with all the injectors firing together to "closed loop" where they fire individually, and if your injectors are cloggo it may simply be starving for fuel once it warms up.
 

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Discussion Starter · #5 ·
Check your fuel trims and see if maybe it's running lean. If so, try running some SeaFoam or Gumout through it and try cleaning your throttle body. The biggest change between cold and warm is that fuel system goes from "open loop" with all the injectors firing together to "closed loop" where they fire individually, and if your injectors are cloggo it may simply be starving for fuel once it warms up.
When the car shuts down it dies all of a sudden…no shutter or nothing…I would think that if it were starving for fuel it would run roughly then shut down
 

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When the car shuts down it dies all of a sudden…no shutter or nothing…I would think that if it were starving for fuel it would run roughly then shut down
Right after the engine shuts down, you'll have to determine if there's an ignition or fuel delivery problem:

* Testing fuel delivery:
An easy way to test the fuel pump and filter is to disconnect the fuel feed hose from the fuel rail and connect it to a long length of spare hose with the other end draped over the fender going into a catch can placed on the ground. Now turn the ignition key to the run position but DO NOT TRY TO START THE ENGINE. You should see fuel going into the can at a good rate for several seconds.

Tee-in a temporary fuel pressure gauge between the fuel feed hose and the fuel rail. If the engine is unable to start, turn the ignition key to the run position but DO NOT TRY TO START THE ENGINE. The fuel pressure reading should be around 51 psi which would be a static reading.

The fuel injectors may not be firing. This can be tested with a "noid" light probe for each injector harness connector.

* Testing ignition:
Pull one or more coil packs to test; use a spare spark plug in the coil pack to test; ground the plug base with a jumper wire to the engine block; see if you're getting a spark while trying to start the engine.
 

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Discussion Starter · #7 ·
Sorry it’s taken a while to reply…so I’m not getting spark when it shuts down….but as soon as it cools down spark comes back
 

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Discussion Starter · #8 ·
Right after the engine shuts down, you'll have to determine if there's an ignition or fuel delivery problem:

* Testing fuel delivery:
An easy way to test the fuel pump and filter is to disconnect the fuel feed hose from the fuel rail and connect it to a long length of spare hose with the other end draped over the fender going into a catch can placed on the ground. Now turn the ignition key to the run position but DO NOT TRY TO START THE ENGINE. You should see fuel going into the can at a good rate for several seconds.

Tee-in a temporary fuel pressure gauge between the fuel feed hose and the fuel rail. If the engine is unable to start, turn the ignition key to the run position but DO NOT TRY TO START THE ENGINE. The fuel pressure reading should be around 51 psi which would be a static reading.

The fuel injectors may not be firing. This can be tested with a "noid" light probe for each injector harness connector.

* Testing ignition:
Pull one or more coil packs to test; use a spare spark plug in the coil pack to test; ground the plug base with a jumper wire to the engine block; see if you're getting a spark while trying to start the engine.
When it shuts down there is no spark…once it sits about 20min spark comes back
 

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Discussion Starter · #10 ·
That sounds awfully much like a cranky crank sensor. When you replaced it, did you use Nissan OE or aftermarket?
The first one was a cheap one offline… the second one I bought at advanced auto I don’t believe it was oem…I’m to the point I’m about to scrap it…just blows my mind that it had a code for the crank sensor I changed it and no more codes would think if it wasn’t working properly it would throw a code.
 

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just blows my mind that it had a code for the crank sensor I changed it and no more codes would think if it wasn’t working properly it would throw a code.
You have to understand the way the ECM's pea-brained little mind works. It looks for signal transitions, and if it doesn't see any then it assumes the sensor is dead and throws a "flatline" code. That's fine as far as it goes, but it doesn't account for a sensor that sees the proper tooth count most of the time but occasionally misses teeth, or that misses teeth at cranking speed when reluctance of the wheel is low but "wakes up" and reads properly once the engine fires and the faster-moving reluctor produces a better signal. Both of those are common failures with cheap aftermarket CKP's. I'm not a bit opposed to aftermarket for most of the parts on a car, but for CKP's and CMP's, save yourself a pile of grief and stick to OEM.
 
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