1999 1.8t auto w/ tip 100k
this only happens when i come to a stop where the rmp would dip down to 200-300rpm then up 1200rpm (car jump forward a little) back down to normal at 700rpm. When making a hard stop, it becomes worst. The rpm would dip and jump but it will not go back to normal. Car would surge constantly. It is worst when i turn on the AC. I have to restart car to put it back to normal. while decelerating, the tranny tends to downshilft within the 1000rpm-2000rpm. is this normal? it seems like the car is still in gear while i am breaking.

previously it had a oil leak in one of the spark plugs. i changed the valve gasket and changed all new spark plugs.
i also try testing my maf by unpluging but no difference.
could it still be the maf or is it a transmission related? there is no cel and the tranny lvl is right.

 

A throttle body alignment could help (if you're 1999.5). Search for that. If not, I don't know what to suggest other than checking for loose hoses under the hood and having it scanned at AutoZone (free). If you get codes, post them or search for them here.

 

In D, you know how when it is decelerating, the rpm is slightly above idle rpm because it is downshifting with the gears. When you hit a dead stop it should go into neutral. In my case, when I do a hard dead stop, it does not go to neutral. Instead, it you will see the rpm drop to 200rpm and back up. After that it seems like the gear is jam which is giving me a surge erratic jerking when I step on the gas. And restarting the engine is my only option to put it back to normal.
the car is not giving me any codes, i had it scaned by a mechanic. i did a throttle body alignment and also took it apart and clearned it. i am pointing at the speed sensor and maf. any ideas?

 

my car was doing this then i went and got the throttle body aligned. now its a lot better and almost normal. i still get a little drop, but i need a new MAF is that helps