# 2008 350Z wont start



## Ron M (Dec 17, 2018)

Hello Everybody, I am working on an 08 350z for a good friend. I am a well seasoned mechanic, but this one seems to have me stumped. It has the security light flashing but goes off while cranking. While cranking, the tachometer does not move. I have checked for spark during cranking and it seems very weak. It has fuel, and fuel is present at the pressure regulator. Fuel is NOT present at the pressure test port. While cranking I have tried using starter fluid with no luck. I think I have listed all the things I have tried so far. I'm trying to stay away from the dealership if possible. Thanks in advance.


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## Ron M (Dec 17, 2018)

Ok so I have a couple of additions to the list of things I have tried. Today I replaced the crank position sensor and all of the cam position sensors. I am still notable to start and also noticed the tachometer isn't moving at all, even during cranking. I'm really stumped now. I'm open to any ideas. Thanks


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## rogoman (Dec 16, 2004)

One of the first things to do is perform an ECU code readout with a portable scan tool to see if any fault codes are set. The tool can be purchased at most auto parts stores. Post the actual codes here on the forum so that we may be able to help you further. If there is one or more fault codes set, they can help point to the malfunction. If you have a copy of the FSM for your vehicle, the code readout procedure is described there along with a listing of codes. You can download a copy of the FSM from these web sites: https://ownersmanuals2.com/ or the Nico Club web site. The section EC.PDF is the one you need to read.

At this point you'll have to determine if there's an ignition or fuel delivery problem:

* Testing fuel delivery:
First check the fuel pump fuse which is 15 amp.

An easy way to test the fuel pump and filter is to connect a long length of spare hose at the pressure test port; 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.

Connect a temporary fuel pressure gauge at the pressure test port. The reading at idle should be 51 psi.
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 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. 

* The cam timing may be incorrect:
Check for a broken chain guide. If the engine uses a timing belt, see if it's broken or it may be cracked and has skipped some teeth.

* There may be a major intake system vacuum leak:
To check the intake system for a vacuum leak, attach a vacuum gauge to a full vacuum source. With the engine fully warmed up, the reading at idle should be 18 - 20 InHg. At 3,000 RPM, it should be 21 InHg.

If readings are under 18 InHg, check the intake manifold nuts to make sure they are tight. The gasket may have failed; spray a water mist at the gasket to see if the gauge reading changes. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.


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## smj999smj (Jan 1, 2006)

With the security light flashing, I would want to check the BCM for trouble codes to make sure it's not an immobilizer issue, which will disable to fuel system when activated. That would require a capable diagnostic tool, however.


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## Ron M (Dec 17, 2018)

Update: I had the car towed to the dealership for diagnostic. Before they pushed it in their shop they tried to crank it. It fired right up! They ran the full diagnostic and found a blown head gasket but NO CODES! I didn't want to drive it with a blown head gasket so I had it towed home. After unloading I tried to start it to get it into my shop to do the head gaskets. The D**N thing wont start again! REALLY?! It cranks and sometimes acts like it wants to start but nothing. I have tried starting fluid, and still nothing. Am I overlooking something obvious?


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