Hi everyone
I did some searching on the forum but I could not find an answer. I have an 08 G35 sedan. This car has limited power or limp mode and has white smoke that takes time to dissapate. I have two codes on the car. P0300 and P0153. I hope that I do not have a major problem. When I press the gas, i do not feel much power. From the time when I start the car, I have white smoke and there is more coming out out of the exhuast. There is no over heating or any other issues. Any help? Thanks

 

Random misfire and bad A/F sensor, the culprit likely stems from the bad A/F sensor giving the P0153 code. Are you consuming any coolant or is the level in the radiator AND the reservoir still on the normal mark?

 

Yes. i am consuming coolant. Would that be causing the smoke and low power? and A/F sensor is oxygen sensor correct, I ordered new sets so i can replace it myself.

 

If you're consuming coolant and are blowing white smoke I can almost guarantee you blew a head gasket. Pressure test each cylinder with a leakdown tester, you will probably have one cylinder that is much lower.

You could also pressure test the coolant system and check it for leakdown but you could probably also just take a flashlight and physically look in each cylinder with the sparkplugs removed and watch coolant spraying into one cylinder.

This is likely also causing the P0300 random misfire code because the bad cylinder probably isn't firing anymore.

There is also a chemical dye test.

 

thanks i will look into this as well.

 

Hope and pray that's not the issue because if so you'll need another motor.......

 

Maybe not, a blown head gasket can be caused by many things including the head warping from a slight overheat. Many times if that's the case you just get the heads decked, slap on a new gasket, problem fixed.

Yes I made that sound really easy, keep in mind this is a DOHC V6 with a LOT of parts to disassemble/reassemble and TTY head bolts.