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Help! Car won't start

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Old Jul 21, 2009 | 12:16 PM
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Default Help! Car won't start

I need some ideas trouble shooting this problem. I have an L33 that I've dropped in my 97 Nissan 240sx. I was suppose to drop the car off this morning to have the exhaust built but the car won't start. PCM has been rewired as a stand alone and the Vatts and all emissions have been removed. This will be my first startup. On friday the engine was in and I was sorting out some fuel issues. Fixed the fuel issues and went to start her up and I had spark, back fires and it little bit of flames coming out of the short C6 Manifolds.(I hadn't stalled the 02 sensors yet and there was some excess fuel from the fuel fileter problem.
Fast forwarding to today, I pulled the engine due to a leaking slave cylinder and I rewrapped the harness to make things fit a little tighter. Now the engine is back in I have fuel, but no spark.
I've checked my grounds and they're all good. Checked the pink wires at the coil plugs and I have power. I've also check the crank sensor behind the starter and it's good. What am I missing? I really don't want to pull this entire harness off again.
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Old Jul 21, 2009 | 12:41 PM
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-Does your fuel pump run for a second or two when you turn on the key?
-Is there pressure at the rail?
-Is the VATS powered and connected still (if you are using a stand alone box)?
-Is the PCM seeing power?
-Any codes?
-All your gounds to the sensors, ignition and PC correct? Did you check them at the PCM harness? At each sensor?
-Are your sensors getting 12V or 5V power as required?
-Have you put a noid light on one of the injectors to see if it is getting signal?
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Old Jul 21, 2009 | 12:56 PM
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Originally Posted by dpd069
-Does your fuel pump run for a second or two when you turn on the key?
-Is there pressure at the rail? Yes, I have pressure. Checked with the shrader valve.
-Is the VATS powered and connected still (if you are using a stand alone box)? Another member here on the forums removed the Vats
-Is the PCM seeing power? Not sure how to check.
-Any codes? UBD2 port is not connected
-All your gounds to the sensors, ignition and PC correct? Did you check them at the PCM harness? At each sensor? Not sure how to do that.
-Are your sensors getting 12V or 5V power as required? Don't have to tools to check.
-Have you put a noid light on one of the injectors to see if it is getting signal?
Yes, I put the light on the pink wire on the injectors and coils and they are both getting power. How would I check for signal?
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Old Jul 21, 2009 | 06:28 PM
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Good and bad news. I found out that the Cranksensor, Camsensor and Map sensor all look a like. Apparently the Cam sensor plug was plugged into the Crank sensor and vice versa.

Bad news is that car still won't start. It cranks, sparks, pops and backfires, but no dice. Even burns off a little of the old bad gas that was in the tank to begin with and that leaked onto the manifolds. Suggestions??
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Old Jul 21, 2009 | 08:02 PM
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Any ideas? I just went and got a couple of gallons of gas, because I push the shrader valve and foam came out.
I put the gas in the tank and I've tried cranking the engine and still nothing. Backfires and pops. I even had to blow out a flame coming from one of the manifolds.
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Old Jul 21, 2009 | 09:53 PM
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Anyone???? Could it be clogged injectors or something? What whould cause the backfiring and poping?
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Old Jul 21, 2009 | 10:12 PM
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How long have the injectors been sitting?

If the fuel line was open, they are probably full of junk and varnish.

My LS1 coughed and sputtered and ran on a couple of cylinders for several minutes and never did run right until I pulled the injectors and took them down to have them ultrasonic cleaned and flowed. It sat for about a year with the line open to the rail. It ran perfectly after the injectors were cleaned.

You might try taking the injectors out and filling them with Seafoam and let them sit upright in a tray of Seafoam for a day or so and then blow them out with carb cleaner and see if that helps.

You can also take them to a fuel injection service and have them cleaned and flowed. Costs around $75 here.
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Old Jul 21, 2009 | 10:38 PM
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I have no idea. I picked up my L33 from a junkyard and had to swap all accessories and intake to the F-Body. I emailed the guy I bought them from a couple of hours ago, but he hasn't responded yet. I do know that he said he pulled them at 35k miles. The fuel rail and injectors came together and they weren't sealed up or anything.
Not to mention I picked up my 240sx from a little hole in the wall dealership that said the car had sat there for 4 years due to a bad fuel filter.
My neighbor had my hook up the fuel pump and pump all the 4 year old gas out into a 5 gallon bucket, but that was after I tried starting the engine about 20 times. The gas smelled horrible and had my whole house stinking for 3 days.
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Old Jul 21, 2009 | 10:56 PM
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Just thought of something else that I thought I might add. Ofcourse by now, you guys can tell that I'm not a mechanic, but I'm trying to learn.

I thought the it was vapor-locked on Friday, because it became really hard for the engine to turnover, then the starter jumped off the flywheel and would just spin. So, I pulled all the plugs and turned the engine over by hand a couple of times. Everything seems to be fine now. One thing that I did notice was that all the spark plugs on the pass side of the car were covered in carbon and smelled like nothing but bad gas and the 3 of the 4 spark plugs on the driverside were pretty clean, but still smelled like bad gas.

Last edited by gjohnson; Jul 21, 2009 at 11:10 PM.
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Old Jul 22, 2009 | 11:04 AM
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If it is firing at all then your PCM, ingition and pump are all working ok.

Your injectors are all gummed up

You probably didn't do yourself any favors by trying to pump old gas through the system. You may have saturated the filter with crap by now too.

I'd take the fuel tank to a radiator repair shop and have it boiled out, replace the filter, flush the fuel line and have the injectors cleaned and you should be ok
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Old Jul 22, 2009 | 11:09 AM
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PS - Your engine isn't 'vapor locked'

To vapor lock it would require heat, and you don't have any yet. Even if it was running you couldn't vapor lock fuel in the rail at 52-3 psi.

You might have some air in the fuel rail though. You might try bleeding it with the schrader valve a few times to get the air out of the rails. Make sure you dry any gasoline before you try and start it.
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Old Jul 22, 2009 | 01:06 PM
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Ok, so if it's firing at all then the PCM, ignition and pump are all working? My neighbor was thinking that maybe some of the injectors or coils were not getting the signal. Would the PCM allow some of the injectors or coils to fire if 1 or more where grounded out or simply not working?

Originally Posted by dpd069
If it is firing at all then your PCM, ingition and pump are all working ok.

Your injectors are all gummed up

You probably didn't do yourself any favors by trying to pump old gas through the system. You may have saturated the filter with crap by now too.

I'd take the fuel tank to a radiator repair shop and have it boiled out, replace the filter, flush the fuel line and have the injectors cleaned and you should be ok
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Old Jul 22, 2009 | 01:29 PM
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I read your post again and it said you could smell gas in both banks of cylinders which led me to the conclusion that the injectors were firing on both sides.

It could be you don't have ignition on one side.

Pull a plug on the side you suspect isn't firing and ground it on the valve cover with the high-tension lead attached and turn the motor over with the starter. You can see pretty quickly if it is firing on that side.

Just because your fuel pump is working doesn't mean you have eneough pressure on the rail. The filter might be so full of junk it is dropping the pressure to the rail. What are you using for a FPR? Do you have a fuel injection quality filter? Where is it located?
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Old Jul 22, 2009 | 01:52 PM
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PS - The suggestion for checking igntion I have above is kind of crude.

Autozone has wiring diagrams that are very easy to read and you can download for free.

Find the circuit for the ignition and buy a $3 Harbor Freight meter and start checking
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Old Jul 22, 2009 | 08:31 PM
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Well, tried to do some trouble shooting tonight, but when I went out to inspect the funny grinding noise the starter was making I found that one of the mounting points had snapped off. Looks like I can't do much tonight. My neighbor and I did pull up the fuel rail and we jumped the fuel injectors to see what we had. All of the fuel injectors sprayed but 1 so it looks like the injectors are not the problem.
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Old Jul 22, 2009 | 09:46 PM
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What stands out to me is that you "re-wrapped the harness"... maybe you missed something when you did this.

Just go back over everything w/ a DVOM and make sure everything that is supposed to have power does and everything that needs to be grounded is. Check at each plug for the coils & injectors.
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Old Jul 23, 2009 | 06:20 AM
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I have a friend who had similar problems with an lt1 . He was going crazy trying to figure it out, turned out to be a voltage problem off the battery. You can buy a cheap multimeter from radio shack. JOHN
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Old Jul 23, 2009 | 08:00 AM
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We were checking some of the wires for power on Tuesday and I have a brand new battery. I believe it was setting at 15 volts off the battery.

I'll check the harness, but does the LS1 starter need any shims? Are all the L series starters the same? My engine, T56 and starter all came from different yards and my neighbor mentioned that I may be having issues with my starter because I don't have the necessary shims.
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Old Jul 23, 2009 | 02:58 PM
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Also, I'm racking my brain trying to figure out what the issue could be and I was thinking that maybe my Cam is throwing everything off. I swapped the L33 cam for a Zo6 cam and Springs while the engine was out, but the PCM was reflashed for my swap and the Z06 Cam. Does it sound like there could be a learning issue for the PCM?
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Old Jul 25, 2009 | 01:08 PM
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Anyone???? Could the Cam swap require different timing?
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