History: My 2008 Infiniti G37s had been having a few rough starts where extra air (press pedal) was needed to get it going on cold days. This had happened maybe 4 or 5 times over the past winter and never before that. The weather has warmed up now and I hadn’t experienced any signs of that issue for about a month.
Trip: I started the car, drove it approximately 400km, car sat two nights, drove 400km home. My parking spot was taken, so I parked a few spots down. Next morning I started the car and moved it 40 feet to my spot, and left it for the day. The following morning I went to start it for work and the rough start condition occurred, but this time it wasn’t solved by pressing the accelerator…
Now: It has been a week and the car cranks but does not start. I have pulled out the back seat to check the fuel pump, and it is working fine, I replaced air filters (just to be safe), and cleaned throttle bodies. I pulled the plugs to take a look and 3 out of 6 plugs were wet, but I am partially dismissing this since I was likely slower getting to the 3 dry plugs. But if you think it is significant, the 3 wet plugs were all on the same bank. I cleaned the plugs of deposits with degreaser and a brass brush and put them back in. Tried starting again and no luck. Ran a program to check for codes, and none found, but this is typical if the car wont start I was told. The battery has run down a few times and had to be disconnected to be charged – car is now likely in learning mode again. When installed and tested on car it shows 11.68v. I purchased starting fluid and introduced a shot yesterday evening, first shot did nothing, second shot started the car… car ran very rough (almost like missing on 3 cylinders - maybe wet plugs were not a coincidence). Ordered new plugs, they will be here tomorrow, this could be the cause of the rough idle, but likely not the failure to start. I have checked all fuses related to fuel pump/injectors/ignition and all are fine.
Any thoughts on my initial no start problem? Fuel pressure regulator or cam/crank sensor? Thanks for the help guys, I appreciate it.