question about maf sensors

Z_ealot

So what about the hesitation and stumbling at idle?

phunk

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

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Z_ealot

does this sound normal to you....

Z_ealot

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.

Ommateal

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

You can check out my post as well... Another insufferable maf code post

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Red 370z Sport 6m
Mods: Stillen 25 row Race Oil cooler|FIXED ESCL|Muffler delete|TEIN Springs|Tint|Varrstoen ES2 Rims|NRG Stealth Knob|Kenwood touchscreen|

jchammond

Someone is selling a nice pair of catch can's for around 3k on here.

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MazWorx built long block | FI-TT-100 Stage 2.75 | IPT built 7A/T

http://www.the370z.com/members-370z-...s-musings.html

Z_ealot

Are they made of gold? lol

jchammond

Not Sure-It's Top Secret Brand.

__________________
MazWorx built long block | FI-TT-100 Stage 2.75 | IPT built 7A/T

http://www.the370z.com/members-370z-...s-musings.html

jchammond

Would not be bad to install a pair;as long as they are functional.
over time the sucked oil (blow by from engine) will gum up in the combustion chamber.
unsure your milage on engine or fuel type/quality being used,,,but i've seen lot's more harm than good from the 10% ethanol blended fuel's.
Ethanol fuel (e-85 etc.) work's great when all supporting components are in place for it & the car is tuned for it.....unsure the shelf life or how long you would want it sitting in your tank;as conventional 10% ethanol gas will begin separating as soon as 1 month (+ or - a bit).
I pay more; but continue my ethanol free93 fuel without problems.
The factory fuel system on these car's don't have a return fuel line-as there was one occasion that i had a stumbling under hard load & not accelerating,,,i checked all known connection's from electrical to vacuum & then removed fuel line to rail & purged out some fuel....thinking maybe got some bad gas-but was all clean.
Car ran perfect ever since.
There are way more skilled & knowledgable people on here that have valid input's.
A little more maintenance is required,but catch can's may be a start to prevent gumming up inside the intake system.
Also a failing or clogged fuel system can cause it to go lean & even show mis-fires.

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MazWorx built long block | FI-TT-100 Stage 2.75 | IPT built 7A/T

http://www.the370z.com/members-370z-...s-musings.html

Z_ealot

Gonna pick up a couple of pcv valves today just as preventative maintenance. I do recall when i had the upper intake manifold off the the chambers on the lower intake manifold leading to bank 2 had quite a bit of oil built up on them while oddly enough the chambers leading to bank 1 barely had any oil build up at all. Not sure if that indicates anything, but still the pcv valves on this car are the originals and the engine has close to 157,000 miles on it. As a side note i have run a couple of cans of fuel system cleaner through the tank before just on the off chance that there was a clog somewhere in the lines back when this all started, but didnt seem to help much

Z_ealot

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.

Ommateal

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.

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Red 370z Sport 6m
Mods: Stillen 25 row Race Oil cooler|FIXED ESCL|Muffler delete|TEIN Springs|Tint|Varrstoen ES2 Rims|NRG Stealth Knob|Kenwood touchscreen|

Z_ealot

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.