RPM dip during WOT

[TheTacoLoco]

Hi all,

Recently purchased a 4BW (A10) and have noticed a dip in power and RPM between 5000-5500rpm when accelerating in 3rd gear. I haven't noticed it in 1 or 2 and I haven't recently had a chance to test higher gears yet.

When it dips, there is a noticeable lack of acceleration and RPM drops to the high 4000s before recovering and continuing to accelerate.

I need to test further, but I was only able to reproduce this while manually shifting, not while in auto.

Has anyone encountered this or have any inclination what could be happening? Car is bone stock as far as I know.

 

[piranha971]

How many miles? Plugs are always the first suspect in cases like this. If the car has been tuned by someone who doesn't know what they are doing with this platform, the throttle would be closing when the peak torque is reached.. IF the car has been tuned.

 

[TheTacoLoco]

How many miles? Plugs are always the first suspect in cases like this. If the car has been tuned by someone who doesn't know what they are doing with this platform, the throttle would be closing when the peak torque is reached.. IF the car has been tuned.

Thanks for your comment. The car has 26,000 miles.

 

[piranha971]

It's a bit early for plugs. Let the dealer figure it out. It's GM's problem for now.