ATIX

Hi everyone! after carefully reading everything I can about the problem & regarding a P0300, I cannot find concluding information on a proper solution.

So Initially I got p0300 and p0301, I swapped the coils 1 & 2 and the P0301 went away, so I'm left with P0300. Car engine lacks power on acceleration (All spark plugs smell like gas) 153 k miles 6 speed manual

-The car starts fine, P0300 code indicates misfire. So I checked:
1. Cleaned the MAF sensor
2. Replaced spark plugs
3. PCV Valve replaced
4. I don't see or hear any leaks (Might have to redo this)
5. Replaced cat with straight pipes (same power no improvement)
6. Checked All coils with multimeter @ 200k OhmsΩ and most are at 123.4 Ohms/1.5 Ohms Except one I only get the reading of 1 Ohm (default value, maybe it's bad)
7. Checked injectors resistance and are all same @ 17 Ohms
8. Checked engine compression @ 190 psi on all

(Should I order a coil Pack?) I read in previous post that some guy mentioned visiting 2 repair shops regarding coils and they usually order a lot of coils for the Z and G35 since they go bad.

-I'm left thinking about testing or replacing the fuel pressure regulator or the Fuel pump due to loss of power according to this post:
https://my350z.com/forum/engine-and-...ml#post8642752

Any help is greatly appreciated please.

(Also here is my extensive troubleshooting log from the previous work I've done on the car:
http://mechanics.stackexchange.com/q...nks-wont-start )

MartinZ

Check the coil with 1 ohm again - could be a bad contact - but if that is the correct reading it's 30% different to the rest which would be a concern

Double check for vacuum leaks - spray degreaser around - if you see bubbles you've found the leak

Check fuel pressure

Run 1 tank with injector cleaner

Bad fuel?

BluestreamDE

My first thought was it might be in Limp Mode. I'd negate your fuel pump as you said you had spark plugs coated in fuel. Sounds like the motor is dumping more fuel then necessary as a safety measure due to something triggering Limp Mode. This is just me throwing my thoughts about the situation.

ATIX

So what would you suggest to attempt next?


Thanks for the info I talked to my cousin and he also told me to check the fuel pressure, and most likely he said it's going to be the fuel pressure regulator going out that's gassing the spark plugs. I'm still in doubt and I hope that's really the problem.

Also last fuel I used was 76 Premium and previously I added a Seafoam into the tank to clean the car.

ATIX

Okay so I talked to another cousin that knows 2 other mechanics, one of them is an expert and Confirmed to replace the fuel pressure regulator.

I searched everywhere on the internet including the forum and there isn't information on testing for fuel pressure. It seems that I have to buy an extension that connects to the stock fuel rail for connecting the gauge =\