2001 R50 Pathfinder hesitation issue

[dwade10]

Hi all

I have been dealing with a hesitation issue for about 6 months that has me stumped. I have an R50 Pathfinder with the VQ35 engine and when giving light throttle during acceleration it will hesitate and stumble like it's losing power at around 2,000 RPMs. If I give it enough throttle off the line it drives normally with no hesitation or downshift. I have taken it to two separate mechanics and both have said the mass air flow sensor is bad and have replaced it. It has never thrown a CEL for this issue, and both mechanics said that when they hook it up to the computer the MAF is flat-lining at around 2,000 RPMS. Each time the issue seems to be fixed but after about 5 miles the hesitation starts again and the MAF fails. Is there an underlying issue that would be causing the MAF sensor to fail immediately?

Thank you!

[barnaclebob]

Those symptoms do match a bad MAF but when mine went bad it threw the bank 1 and bank 2 too lean codes.

[Blindaviator]

Just a thought but did you think about the TPS maybe going bad since you have no MAF codes?

[abnrjd]

Also check your vent swirl control solenoid/valve in addition to your evaporator canister