So at times my car will start up just fine,
but at some occasions it will sound like it started up very weak, and revved to a really low rpm at idle.

I had the 3 sensors in the engine area replaced (couple months ago) as they were all covered in oil, which caused my car to not start up or sometimes shut off while driving.

Is there any reason why it might do this?

 

well considering the cam sensors are in the valve covers, there had better be oil on them. dunno what the 3rd sensor is because if the crank sensor was bad, they car wouldnt start.

Maybe the 3rd is your MAF sensor? You are not really giving us anything to go off of.

If you dont have any codes, it could be anything.

 

What sensors were they? Is your throttle plate covered in oil?

 

Sorry guys, I don't remember too well what censors they were, (Don't know much about cars) I just remember the guy telling me 350z's had 3 censors.

No codes.

It would just start up weak sometimes after a decent drive.

 

WTF? There are WAYYY more than 3 sensors... I'm going out on a limb, but I'm guessing it's the MAF.

 

Lesson learned. If you don't know much about cars, take it to a mechanic. It's cheaper in the end. How much did the 3 sensors you didn't need set you back?

 

^ It sounds like he took it to a "mechanic."

 

it costed about $130
they were all in the engine bay area if that helps.

 

sensors I didn't need?

my car would shut off while driving or wouldnt even turn on.
and replacing the censors fixed it.