Hello everyone, I am posting this on here because I cannot find a solution anywhere and it is incredibly frustrating. I drive a 2004 G35 6MT with around 85k miles, and recently a few things have happened and I have lost power. about a month ago I was driving quickly, and all the sudden at around 70 my car cuts off while im driving and i had to come to a stop and restart it. It turned right back on and ran fine, but I have a power loss throughout the whole RPM band. No codes or check engine light have appeared though. I have brought it to a shop, and they checked the codes, TPS sensor, pedal position sensor, and the MAF sensor, since I asked them to, but could not find any problems with the car. They claim there are no codes and the car seems to be functioning properly. I have cleaned my MAF sensor with the proper maf sensor cleaner, and cleaned the throttle body, and they helped a little bit but have not solved the real power loss problem. Also, I have a loud exhaust on my car and have noticed it has gotten a little higher pitched and raspier in higher RPMs, like its running lean or something. I have also done the ECU reset procedure several times, and a throttle position open and closed reset procedure one time after the initial problem. My olny mods are an air intake, and true dual exhaust with an x pipe. The problems I am having did not occur when I installed these mods. A couple of weeks ago, my car started to run hot, and I stopped and turned the car off before it got too hot. After taking it to a shop I found out my thermostat and housing were going bad so I got them replaced, along with a radiator flush and new fluid, and that problem is gone, but my power loss problem is still there. So far, nothing has helped and im stuck with a slower G35 and cant fix it, so im sure all of you g35 drivers can relate to how that feels. Any ideas? any help would be greatly appreciated.

 

I had the same sort of power loss as well. It was my camshaft position sensors going bad/already went bad. I replaced it and everything was back to normal. Only difference was I had check engine lights on prior to the repair

 

Interesting.. how much did they cost to replace?

 

I had a shop do mine only because I felt it was more of a wiring issue(which it wasn't) they pretty much just unplug and come out-then plug the new ones back in. Driver and passenger side. Very easy DIY though. Hardest part is just reaching them. Tight squeeze at times