Hey guys, need all expert input on this issue. Been trying to trouble shoot this problem for the past week or so. Car lacks acceleration, it feels like the car is in 3rd gear or something trying to accelerate from standstill. It's a auto blm. Either no response or climbs really slow. Car smooths out above 2k RPM.

I know the throttle is opening properly, I've got a vacuum meter, when pedal is press the vacuum drops as it should but car was not accelerating or accelerates really slow like in high gear. Above 2k RPM the car behaves quite normal albeit feels a bit more underpowered than usual. No jerking etc, cars just wont go.

So far I cleaned the throttle body, changed the spark plugs, engine oil and gearbox oil was changed recently. Just serviced the brakes and change fan belt. What else could be causing the problem? Any input? Thanks a lot guys.

Throttle body response normal (according to vacuum gauge), happening as well in L gear means it's probably not gearbox/TCU problem.

In this case I suspect there is something wrong with the torque converter causing slippage during acceleration.