05 G35X 70,000miles

for the last two weeks, when i turn on my car it hesitates to crank but it always does. when the engine finally cranks it stutters and the RPM is about 400-500 for about 1-2 seconds then everything is back to normal.

two days ago i finally got the check engine light. i got two codes. P0300 (random misfire) P0301 (cylinder 1 misfire)

i've done some reading and everyone with this issue usally has some type of loss of power while driving or car in idle.

i have no power loss. car runs fine, no black smoke.

since cylder 1 is pretty easy to access without getting crazy so i checked the coil and the plug for cylinder 1 and everthing looks greats.

anyone got any ideas? car is in the shop now getting fuel pressure test.

one of my buddies also suggested the crankshaft sensor?

 

It could be that, or a camshaft sensor. Other than that you could try to switch the #1 coil to a different location and see if the missfire follows it.

 

Crankshaft sensor, or passenger side camshaft sensor (Passenger side is the straight one.)

 

My mech just called, im loosing all fuel pressure when the car shuts off. Gonna replace fuel regulator for now, if that doesnt solve it gonna tell him to look into the sensor. Is there a way to tell there bad or is it just replace and test?

 

I'm no expert, but isn't it normal to lose fuel pressure when the motor shuts off?

 

Yes, but i was told not all pressure. U still need some pressure for the injectors. His guage waa dropping to zero

 

Finally got around to replace the fuel regulator. Every is fine now. Car starts like a champ again.