i have a single turbo full bridge port. when i get on it or stay on the acclerator constantly the car bucks like crazy. it speeds up falls off and takes off. this really sucks during mid corners and have me puzzled. i missed my last two track days b/c of this and had to drive my honduh.
i had pfs change the coilpacks, spk plug wire and plugs when i had the first problem. it is still doing it. could i have a bad tps sensor???? i usually does it the worst in 2nd gear around 5k and up. my a/f ratios are in the 18-20s when it bucks. do you think the injectors need to be sent out to be cleaned. the fuel filter was also cleaned. thanks for your help in dx this problem in advance. i have mazda drivers @ shanndoh coming up in oct. kvn

 

I had the same problem, it was caused by starvation.
I replaced the injectors and it was gone.

Then it started happening again and it turns out my fuel gauge was completely off. My tank was empty -but I'm sure that isn't your problem.