Driving my son to school the other day and my G37x starts to lose power, gas pedal will not respond. Was able to pull off the road before the car died. I tried several times to start it but she would only crank and not start. Got it towed home and pulled codes for vehicle cam sensor. Replaced both and tried to fire it up but she would only crank, won't start. Read online if you disconnect passenger side sensor car will start, I did this and the car started. Plugged sensor back in turned car off, tried to start but only cranking. Pulled code for crankshaft position sensor, replaced the crankshaft sensor and now the car won't even crank. I hit the push start and the vehicle cluster lights up, radio turns on, etc. Service engine soon light is on, vdc off, and brake. I used all OEM parts. I tried to put the old crankshaft sensor on but still won't crank. I tried to unplug passenger cam sensor and still no crank. I have done the pedal trick to clear the ecu. Nothing is working. Please help!! 2009 g37x 114,000 miles. Thank You

 

i had the exact same engine problem after going to infiniti 3 times in a row they finally found out what was wrong with it the 3rd time their was an issue with the engine harness. My car was at the dealership for 10 hours and they charged me me somewhere around 600 dollars to fix wires.

Have you done maintenance on the following?

Drive belt,
Spark Plugs
Battery

your last resort would be to tow it to the dealership.

 

First off Thank You very much for your reply. I have not done any maintenance on battery, spark plugs or drive belt. What sort of maintenance can I do on the drive belt? Do you know what they did ro the engine harness? I assume that's a stupid question because you would have included that in your reply. You had to pay for 3 tows and $600 to fix it? That sucks man. Any other info you may have is greatly appreciated.

 

Maintenance on drive belt, would be to replace it its suppose to be changed every 60k or so or untill you see that it is worn out. Infiniti techs told me that one of my engine harness wire had gotten stretched out over time and caused multiple engine missfires and service engine lights.

I also had a vacuum leak that cause harsh starts.

 

You can read the FSM manual here

Factory Service Manuals - NICO Club

Telcoman

 

Appreciate the info. Unfortunately I read the manual the day I was having problems and it didn't help. Had the car towed to Infiniti repair shop three days ago and hey haven't found the problem. I have to wait until Monday for them to continue the search. This blows, I need my G back!

 

Final Update
Both cam sprockets need to be replaced and some sort on tensioner work. Not a total loss but hittin me for $3,600. Actually pretty excited to get her back. Should run great after all the work. Been driving the wife's Hyundai Tucson, that thing is a wimp. Hope this info helps someone out.

 

There are 3 tiny pins inside the cam sensor that will bend down if you don't insert the male wired end perfectly straight and you will have to pull the sensor and use a small needle nose to gently re bend the bent pin or the sensor will not read and the car won't start.I learned this when I pulled both cam pos sensor connectors and reconnected them and bent the pins, it's not hard to make this mistake.

 

Thanks for posting the update.
The cam sprockets were replaced because the timing ring slipped:




link to full document: http://www.jimwolftechnology.com/wol...derslipped.pdf

 

What was wrong with the engine harness?