2007 Infiniti M45 with 110k miles
Took it to the dealer, he said it was the throttle body when they ran the code. Still can't get over 40. If I push it which I can, there is a very loud noise and I believe the noise is the trans because it's not shifting. Took it back to dealer and said it's doing the same hing. He said there are no codes not even stored. Can anyone help?

It sounds like the car is in limp mode? Might be MAF, might be TB, might be many things...odd that he is saying there is no codes.

Personally, my hunch would be the MAF (mass airflow sensor). Nissan/Infiniti MAF's are VERY delicate.

Ilya wrote: ↑

Mon Sep 13, 2021 8:07 am

Personally, my hunch would be the MAF (mass airflow sensor). Nissan/Infiniti MAF's are VERY delicate.

+1. Like most N/I models, the WD says your ride has no MAP sensor to allow the ECM to cross-check the MAF. The ECM basically has to trust it. So if the MAF is lying, it will cause all sorts of issues without throwing codes (or even throwing unrelated ones when the ECM can't figure out what's going on). All it takes is a bit of lint or a butterfly wing lodged in the wrong place.

If you do end up replacing your MAF sensor (which you may just be able to use a spray cleaner) be sure and get an OEM one. This is a device that relies on a specific resistance curve and heating potential, and off-brand sensors can throw things off with your engine as well.

EniGmA1987 wrote: ↑

Mon Sep 13, 2021 9:47 am

If you do end up replacing your MAF sensor (which you may just be able to use a spray cleaner) be sure and get an OEM one. This is a device that relies on a specific resistance curve and heating potential, and off-brand sensors can throw things off with your engine as well.

+1 on that also. Aftermarket sensors will usually calibrate okay when you do IAVL, but that's only half the story. The ECM will extrapolate that base reading across the whole RPM range, so if the response curve doesn't match what Infiniti intended, the best thing you can expect is poor performance. The worst can get downright ugly. Don't go there, get the OE part.