I just bought a ‘91 mk3 Supra with a 7m-GTE. The car has a hesitation and starts to backfire once it get into boost not allowing the car to accelerate. But the car had also been converted to a manual r154 from the automatic, and it still had the automatic ECU in it. It has a t61 turbo upgrade and a newly rebuilt engine. It seems to be running fine other than the hesitation. Would this be a tuning issue or an issue with the transmission ECU?