Crank no start? Any ideas/tips...?

[jaworski88]

Can anyone help me please... My 2002 QX4 sat for about 2 weeks while I worked on replacing the valve cover gaskets, in addition to replacing all the spark plugs, ignition coils, both T-stats, and the coolant temp sensor at the rear of engine. After putting everything all back together, now it just cranks over but doesn't start. It used to fire right up! I am pretty sure I put all the connectors and hoses back, as I was super careful and organized. I suspect the fuel pump or the fuel filter as both are original. Is it possible that an old fuel filter can prevent fuel from passing through especially after sitting for a couple weeks? After cranking a few times, there is a slight smell of gas at the rear of the car, but no signs of gas leak anywhere.

Can anyone please point me to a write-up for checking fuel pressure? The FSM says to install a Fuel Pressure Check Adapter between the fuel pressure regulator and the fuel pipe, I have no idea where to get that adapter, so has anyone checked fuel pressure without that. Shouldn't I be able to check the fuel pressure at the fuel filter connection?

Thanks in advance...

[mdmellott]

It smells like you're not getting ignition. Check ignition fuses and connections first. Change the fuel filter regardless. An original filter on a '02 is far past its life expectancy unless you only have like 30K miles on that old timer. Even then, the filter media if not expected to survive decades.

[jaworski88]

Thank you for your response, mdmellot. I've read a lot of your excellent write-ups/advice here, so I appreciate your help/knowledge.
Yes, my plan is to get a new fuel filter on first. While I have it off, would it make sense to install a fuel pressure gauge there to see if the pump is working when turning ignition to ON? I am not sure how to do it according to the service manual at the fuel rail.

All fuses (engine bay) are good. And I made sure all my connectors snapped in. I'm pretty sure everything is connected. Do you know of a way to check the two fuel pump relays (engine bay), like connecting pins with jump wire to see if it's working?

Finally, one thing I noticed now (not sure if it did it before), is that the connector below the throttle body (idle air control valve?) makes a sound for a couple of seconds when I turn the key to ON, then also momentarily makes the same sound after turning back to OFF even after pulling the key out. Is that normal?

This car was running perfectly before this, and I was so careful when doing this job... It's so frustrating...

Thank you.

[mdmellott]

The IACV noises you hear are normal. We just don't typically hear them when the engine fires up and pay little or no attention to it when we turn it off. Another very faint noise you should hear when the key is turned to On, is the fuel pump pressuring. There are fuses under the dash, left lower corner behind the little storage compartment, you should check as well. One is for the fuel pump another for ignition. You can check fuel pressure back by the filter and relays as well if you need to. I'm away from my tools and resources at the moment so I'm just hoping it is as simple as a blown fuse or a clogged fuel filter.

[mdmellott]

I just double checked my Haynes repair manual, compared to the FSM, regarding doing a fuel pressure check. I like the Haynes method better with a tee connector on a fuel pressure gauge, a very short length of fuel line on one leg of the tee, connected to the output side of the filter and the now disconnected fuel line to the other leg of the tee, allows any fuel that comes out of the lines during the hookup process to be caught in an oil drain pan. Much cleaner than fuel getting onto the engine in the limited space within the engine bay.

Check those fuses inside the vehicle under the dash. I've lost track of how many times I've inadvertently blown I fuse on my '02 and other vehicles by not first disconnecting my battery before dealing with electrical components or accidently shorting a component's positive wire to ground with a tool or something else. I hope you get this all sorted out.

[The Grand Pooh-Bah]

Did you disconnect the battery while performing the tasks?

[jaworski88]

Thank you, mdmellot, for kindly taking the time for helping me out and many others here with our trucks. Also thanks for confirming the method of measuring fuel pressure at the fuel filter connection, I am glad to hear that's the method in your Haynes manual. That's exactly how I envisioned doing it, but since I've never done it that way, I was wondering if that's how other owners of this truck has done it. All my other cars have a Schrader valve right on the fuel rail for measuring pressure! I will check the fuses inside the truck, then check for spark and/or voltage at the ignition coils. As you say, I am installing new fuel filter regardless, and will check pressure while I am there. I can't get to it until the weekend, but I'll be sure to let you when I find the problem. Thanks again so much!

[jaworski88]

Did you disconnect the battery while performing the tasks?

Oh yes, I always disconnect the battery when working on anything electrical.

[jaworski88]

Here is a quick update:

Connected Fuel pressure gauge at the exit of fuel filter. Turned key to ON, pressure jumped to about 26-28 psi. After a few more ON/OFF cycles of the key, it jumped to about 42 psi. Leaving it overnight it dropped to about 22 psi.

I was able to confirm that the ignition coil for cylinder #1 is firing. Pulled plugs from cyl #1, #3, #5, and they were all a bit dirty with black carbon powder. A light spray of carb cleaner blew it all right off and they looked brand new again, like they never ignited at all. NOTE: I did put copper anti-seize on the threads when I first installed them (I probably should not have). Cleaned off all the antiseize from threads and reinstalled plugs. Will do the other side this weekend. The plugs were a bit wet and smelled like gas, so it appears that the injectors are working.

My thoughts/questions: These are long shots... but maybe the antiseize had something to do with it, perhaps too much on it??? Or Is it possible that the coils are not seating properly on the spark plugs for whatever reason? They can only go in so far. Note that the valve cover and gaskets are brand new from Nissan. The saga continues...

[VStar650CL]

Md might know better than I do whether there's a return regulator on your rail, but 26~28 psi is way low even with a regulator. Unregulated pumps should put out 51 minimum as soon as you crack the key, most regulated pumps should jump to 40+. That pump is very weak.

[jaworski88]

Yes, it does have a return regulator. There is a fuel pressure regulator with a return hose, and I did mess with that a bit. I unbolted the bracket bolts and moved it around a little in order to get the valve cover off and new one on. I may have messed something up with it by "disturbing" it. So possibly a combination of that and low fuel pressure it sounds like. It's odd that this truck had no issues whatsoever before this major "maintenance" project, she would start up so quickly and run so smooth every time. Now suddenly she's not happy... Thanks for you comment.

[VStar650CL]

To find out quickly whether the problem is the pump or the regulator, repeat the test with the return line pinched off. If it jumps right up to 50~60 psi then the regulator is bad, if it still has anemia then the pump is bad.

[AlanAZ]

My thoughts/questions: These are long shots... but maybe the antiseize had something to do with it, perhaps too much on it???

Copper anti-seize would not prevent the spark plugs from firing, but can cause other problems, it's good you took it off. From the NGK website:

NGK spark plugs feature trivalent plating. This silver or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without lubrication or anti-seize.

Anti-seize can act as a lubricant, altering torque values up to 20 percent, increasing the risk of spark plug thread breakage and/or metal shell stretch. Thread breakage can sometimes involve removing the cylinder head for repair. Metal shell stretch changes the heat rating of the spark plug and can result in serious engine damage caused by pre-ignition. Do not use anti-seize or lubricant on NGK spark plugs. It is completely unnecessary and can be detrimental.

[jaworski88]

To find out quickly whether the problem is the pump or the regulator, repeat the test with the return line pinched off. If it jumps right up to 50~60 psi then the regulator is bad, if it still has anemia then the pump is bad.

Ah that makes perfect sense! I never would have thought of that! So if it jumps up to 50-60 psi with it pinched off, then that means it's a leaky regulator, right? I'll try that... Thank you so much for that tip!

[VStar650CL]

Ah that makes perfect sense! I never would have thought of that! So if it jumps up to 50-60 psi with it pinched off, then that means it's a leaky regulator, right? I'll try that... Thank you so much for that tip!

Correct. You're most welcome!

[jaworski88]

Update... interestingly the problem was a clogged dirty fuel filter! After installing the new filter and priming it, she fired right up! The old girl is back on the road again... Never again will I neglect to change out that fuel filter!

I sincerely appreciate everyone for all your advice/comments, it was all very helpful.