Acceleration stutter from a quick hard stop

F

Fx35-man

Member
Location
Sunnvale, ca
Car
2007 FX35
I just recently noticed a wierd acceleration stutter from a quick hard stop. Basically I would do a hard stop from ~40mph then as soon as I'm stop, I would give it a hard gas to accelerate and that's when I noticed the stutter vibration (like as if the transmission is trying to catch up) before it starts going. Under normal driving I never encounter the same stutter. Is this normal? Also this is an AWD model.
 
Hm.. I always do this on highway when I decrease the speed to pass the ezpass booth and press the gas pedal all the way to make it floor. I've never had stutter vibration when flooring the car... (I also have the AWD model 05 FX35) It will be helpful to others if you could post a video... I hope it gets solved.. Good luck
 
I had a fairly similar issue once. It just happened one day that any time I would hit the gas hard the fx would stumble a bit before taking off, sort of like the timing was off or something.
Short answer: Vacuum leak in the intake tract.
Long answer: Upon closer examination it turned out to be a loose hose clamp between my MAF sensor tube and the engine side of my intake tube. (I was messing with the intake tract a lot at the time, taking it off every day or so for measurements and the like...) Anyway, the loose clamp was allowing air to be sucked into the plenum without passing by the MAF sensor, which was throwing my AFR off and causing the "bogging" under heavy acceleration. I tightened up the clamp and all is well.

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Well I finally figure how this stutter acceleration got started. It was a stupid mistake on my part but I thought I'll share it in case anyone else comes across this.
A few days ago I decided to do a transmission fluid change and did the usual drain and refill. When filling the new fluids back, I would guage how much more was needed by using the dip stick in the charging tube. The problem was I was reading the dip stick incorrectly. When checking the ATF level, the car needed to be running. I was doing it while the car was off and the level indicated full. I finally caught the problem and when checking it again with the car running, it was way low. After adding another quart and a half, to my relief the FX is finally shifting correctly. Short on a quart of fluid makes a huge difference.
 
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I had similar issue as you, so I brought my FX to my dealer,
and they removed and lubed both rear axle splines, and problem sloved.
And I did this under my extended warranty.
hope it helps,
 
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