Nissan Repair Questions? Ask a Mechanic for Answers ASAP
Do you have a scan tool to check for communication with the computer?
No codes, that's good, but it does seem to be communicating correctly?
Can you see RPM data while the engine is cranking?
Does the RPM signal seem steady or jumpy?
Might not be a bad idea to replace the cam position sensor. It's not a definite cause, but if the RPM signal isn't just right it won't provide a good injector pulse.
If you spray supplemental fuel in the intake will the engine start and run for a few seconds?
Fuel, compression and spark and it doesn't run? That doesn't make a lot of sense.
I'm sorting through the Nissan tech database to see if anyone else has experienced something like this.
It seems like you are getting good communication with the ECM right?
Here is what the tech line says to do to make sure the ECM isn't dropping out when cranking:
1. Backprobe and check for good battery voltage to the ECM on the Orange wire in terminal 93 with the key on. Key on battery voltage on terminal 93 tells the ECM to ground the ECM relay on the Pink wire in terminal 32.2. Backprobe and check the ground for the ECM relay on the Pink wire in terminal 32 - look for 12 volts with the key off and look for less than 1.0 volts (usually about 0.8 volts) with the key on.3. Backprobe and check the ECM grounds on the Black wires in terminals 10, 11, 108 - look for 0.05 volts or less
Let's try resetting everything. Maybe it's a PATS key issue and it's actually cutting the spark or injector pulse but doesn't seem like it.
Pull both battery cables and then touch them together for about 1 minute. This will draw down all of the power in the modules.
Then hook the battery back up and put the key in and turn it to on for 5 seconds, then off for 10 seconds then run for 5 seconds then off for 10 and then try to start it.
If it floor it, the computer shuts off the fuel injectors. It's a test mode that all newer vehicles have.
After cranking it a bit are you getting any codes?
Does the pressure drop below 200 kPa (29 psi) 30 minutes after engine shutoff?
Was it lower than 29psi?
Ok. I don't know what is left to check. I can send your question back out to the group and see if anyone else has any insights, but it just doesn't make sense to have injector pulse, spark, compression, PCM communication, and crank and it still won't run. It has all it needs.
It's not really all that common for them to go bad. If they do they give the same symptoms you describe, but typically you can see the bad signal on your RPM data. I suppose it's possible that the scan tool could be not sensitive enough to pick up a fault.
Please let me know if you need additional help. Don't forget to rate.
If you have a lab scope you can look for a good solid square wave signal from the sensor while cranking. If not, you can look for a steady RPM signal on your scan tool graphing function when cranking.
Other than these two methods there is really no other way to test it.
Try pulling the fuel pump relay and then starting it on supplemental fuel sprayed down the intake. It's possible that the fuel pressure regulator is faulty and is dumping too much fuel, flooding the car. This would normally set trouble codes, but maybe the computer doesn't have a chance to pick it up since it won't actually start.
Also, when you have tried starting it with the pedal to the floor, while cranking, let off the pedal. Does it stumble and almost start?
It's either flooding out or not getting any spark if the plugs are wet. I would say not getting spark since pulling the fuel pump fuse would stop it from flooding and likely start for at least a few seconds.
I think you might need to throw a cam sensor at it.