So I’ve seen a few people touch on this before, a few days ago I got the p0340 code for the passenger side camshaft position sensor and the car was hard starting. Went to autozone, got the part and installed it that day. Problem solved. But after driving it to operating temp and parking it, I tried to restart it and The RPMs dropped super low and it almost stalled out. It drives perfectly fine, it’s just on warm starts it wants to stall out. Cold starts are fine, I took the part back and got one from the Nissan dealer ($180!) and installed it again. Now I’m STILL having the same stalling on warm start issue and I’m getting no check engine light, I’ve also reset the ECU twice with no luck. Should I replace the driver side sensor too or take the car in to get looked at I have no idea what the problem could be, it’s highly unlikely that I got unlucky and got TWO bad sensors out of the box but possible? Any ideas? It’s a 2004 g35 sedan, I got the water pump replaced exactly a week ago could that also be a source of my problem?

 

Common issue for these cars is that the cam position sensors fail. However, its just as common for aftermarket cam sensors to fail as well-
Most recommend either the OEM Nissan/Infiniti cam sensors or the Hitachi ones. I believe Hitachi is the OEM manufacturer for Nissan.

 

Pull and inspect the plugs, if it runs fine cold but starts misbehaving hot it's probably not a cam sensor issue. Vacuum leaks can also be made worse when things heat up and cracked rubber softens and lets more air through.

Did it ever run correctly when you got it back from that water pump fix? They may have damaged something like the intake pipe, not tightened up a clamp, etc.

 

It seemed to run ok once I got it back after the water pump fix, and i made sure to get an OEM Nissan sensor from the dealer. I’ll be sure to check all the connections but it seems a little different than a vacuum leak. i Just saw another thread where somebody described the exact same issue, they recommended cleaning the TB and doing the pedal recalibration might try that as well.

UPDATE: thanks for the suggestions, after googling and reading similar threads I got some TB cleaner, cleaned the TB and did the idle relearn and now everything seems ok.

 

Clean the throttle body, I know Maxima's are notorious for this exact issue due to dirty throttle bodies. But make sure you do it right, don't move the throttle blade manually.