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Hello All - new to the forums, I apologize in advance as I'm 100% not as technical with vehicles as most are here. Friend at work told me to check on these forums for similar issues I'm having with my Pathfinder to troubleshoot the problem. My Pathfinder has ran AWESOME to this point ( purchased in '09 ), has 188k miles on it, never had any MAJOR repairs done to it, ( check engine light has been on due to code P0463 - just dealt with no accurate gas level readings on dash for a while now ) just your typical maintenance. In the past month though, the car would die randomly while driving down the road/freeway, I would pull over, wait 10 seconds, crank the key, car would start and off I would go. Recently, it only runs for about 25 minutes then just shuts off and wont start again ( wait an hour, car starts, dies 25 minutes later ). I pulled the codes from computer, received P0463 - fuel level sensor circuit high input & P0340 - Camshaft Position Sensor Circuit malfunction. Checked recalls from Nissan, my VIN wasn't part of the national recall for Fuel Level sensor circuit high input. So off I went doing research to fix issue rather than taking it to a shop and spending arm/leg for trouble shooting/repairs. I started out by replacing the Cam & Crank sensors with OEM parts, drove down to auto parts store, P0340 is no longer there, just the P0463 code. Rather than just replacing the fuel level sensor by itself, I just replaced the Fuel Pump assembly all together with OEM part. After installation, ran for 25 minutes and died. Waited 10 seconds, car cranks but wont start - same issue as previously. Check engine light is back on, haven't ran car down to auto parts store to get code ( just installed Fuel Pump this evening ). Any help/ideas/troubleshooting guides would be greatly appreciated - I know most will probably say take it to a mechanic to get resolved but I'm trying to avoid spending $500 - $1k for labor cost - I may only have this vehicle for another 6 months at most when we purchase an Armada.
 

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Sup Mod keeping the peace
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I just replaced the Fuel Pump assembly all together with OEM part. After installation, ran for 25 minutes and died. Waited 10 seconds, car cranks but wont start - same issue as previously. Check engine light is back on, haven't ran car down to auto parts store to get code ( just installed Fuel Pump this evening ). Any help/ideas/troubleshooting guides would be greatly appreciated.
At the point when you're unable to start the engine, 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 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. 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 several 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.

* There may be a major intake system vacuum leak. Check the intake manifold nuts to make sure they are tight. The gasket may have failed. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.

Go get your code readout done. It might be a new fault code that could give some insight into the problem.
 

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Discussion Starter #5
At the point when you're unable to start the engine, 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 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. 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 several 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.

* There may be a major intake system vacuum leak. Check the intake manifold nuts to make sure they are tight. The gasket may have failed. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.

Go get your code readout done. It might be a new fault code that could give some insight into the problem.
Thanks for the great advice/insight rogoman. I went ahead and tested the fuel delivery you recommended - my 5 gallon home depot bucket started catching the gas - so it looks like the engine is getting its fuel. I did not a have fuel pressure gauge to test the PSI coming from the hose.

You think the fuel injectors could be the problem even if the cars running for 25 mins? The cars idle is fine while the engine is running, doesn't idle rough or run rough, during those 20-25 mins of run time car runs/sounds like it always has.

I went ahead and pulled the check engine light code, received code P0335 Crankshaft Position Sensor A Circuit Malfunction - which is odd because I replaced the Crank & Cam sensors as soon as I started having this issue. I'd like to rule out that its a bad Crank sensor since I just replaced it, could it be the wiring harness? Short to Ground? Reluctor ring problem? Whatever the problem is here, it takes 20-25 minutes for SOMETHING to get "hot" in the engine to cause the engine to turn off/stall. Does that sound like a short?
 

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Sup Mod keeping the peace
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Like I posted earlier: "At the point when you're unable to start the engine, you'll have to determine if there's an ignition or fuel delivery problem". You need some basis to start from to try to pin-point the problem. Another quick test that you can do is by first removing the air intake hose that connects to the throttle valve; then spray some carb cleaner into the throttle valve. If the engine starts up just for a few seconds, that tells you that the ignition is OK; so now you know there's a fuel delivery problem.

There's two wires to each fuel injector; one is the signal wire and the other one should have a constant 12 volts. First make sure you have 12V at every fuel injector. Then by using a NOID light, determine if you're getting signal pulses at each injector. Inspect all the engine harness ground points for tightness and any oxidation. Lastly check the fuel pressure; you may have a bad FPR.

Finally if every else checks out OK, then the ECU may be prime suspect. Since it's located in the engine compartment on the passenger's side, it may have become sensitive to a buildup of heat, so at a certain point of operation it fails; after it cools down, it's working OK.
 

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NF Mod/Nissan Master Tech
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If it's a VG33E engine, the crank sensor (the one on the transmission bellhousing) is only a monitoring sensor for the ECM and doesn't affect engine performance. Sometimes that will get triggered as a by-product of a bad distributor. If you can duplicate the no-start and can verify no spark to the plugs, it's likely the distributor. If it is that, I highly recommend you get a genuine Nissan reman as the aftermarket units tend to be "hit or miss" as far as quality and longevity.
 
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