Nissan 370Z Forum - question about maf sensors

Nissan 370Z Forum (http://www.the370z.com/)

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- - question about maf sensors (http://www.the370z.com/engine-drivetrain/122400-question-about-maf-sensors.html)

Quote:

Originally Posted by phunk (Post 3672675)

I haven't seen that yet so cannot really comment. Sounds normal in the PCV video though.

does this sound normal to you....

Quote:

Originally Posted by phunk (Post 3673370)

Yes? Who cares what it sounds like when you shake it? See the service manual for details on how to test it. You originally asked if its supposed to flow under vacuum at idle, and the answer is yes. Thats exactly what its supposed to do. I also showed you a screenshot from the service manual stating the same thing. As for your video, both the new and the old one sound identical... so I am not sure what its supposed to prove. But I have some valves here off a perfectly running Z and they dont make that noise at all. So you tell me what sound is normal.

I dunno, but the fact I had to shake the old one pretty vigorously in order to get it to rattle like that says a lot to me compared to the new one which I barely had to put any force into In order for it to rattle like that. in any case I would rather have new pcv valves than ones with almost 157,000 miles on them and no history on the car of whether the oil was changed on a timely basis to prevent the valves from gumming up in the first place if they ever had.

Quote:

Originally Posted by Z_ealot (Post 3673375)

:tup: :tiphat:

Quote:

Originally Posted by Z_ealot (Post 3673375)

... I would rather have new pcv valves than ones with almost 157,000 miles on them and no history on the car of whether the oil was changed on a timely basis to prevent the valves from gumming up in the first place if they ever had.

:iagree:

At 30K miles, I might just spray some carb cleaner through them. At almost 160K miles, it's time to replace them.

Quote:

Originally Posted by Z_ealot (Post 3672671)

So what about the hesitation and stumbling at idle?

Welcome to the 'messed up, hesitant, impossible to diagnose, Z club"

You can check out my post as well... http://www.the370z.com/intake-exhaus...code-post.html

just an update....after I changed out my pcv valves I now see my fuel trims in opposite positions at startup. before changing out the pcv valves on startup my LTFT would be at -10.94% with STFT trending towards +9%. once warm with the old pcv valves my LTFT would stay stuck at -10.94% with STFT at around +3% or close to 0%, when I would snap the throttle open LTFT would stay pinned at -10.94%. now with new PCV valves on startup my LTFT is now at +9% and STFT is at a -10% until warm up when LTFT seems to settle at around -8% and STFT seems to settle around 0%, interesting to note however is now when I snap the throttle open all fuel trims line up at 0% or close to it and go back to the previous figures when let back down to idle. not to jump to any conclusions, but to me at least the old PCV valves seem to have been the culprit when it came to the fuel trims seeing as everything is now lining up with the new PCV valves.

Quote:

Originally Posted by Z_ealot (Post 3674130)

That's great to hear, keep us updated to make sure this is a long term fix for your issue... Not sure if it will help me but I might change mine just because i'm paranoid that ANY part could be the problem for me at this point... sigh. I wouldn't be surprised if they blamed my issues on a slightly loose fender bolt.

Quote:

Originally Posted by Ommateal (Post 3674721)

Drove her today and fuel trims are still getting better, down to about -7% on long terms with short terms staying near 0 at idle. Still have to torque down the pcv valves to the correct torque, but with just tightening them by hand as much as i could without overdoing it the car is now stable and the stumbling at idle is gone as well as the slight misfire and hesitation i was getting.