91 series 5 turbo stock ecu fmic with pod

The car starts fine but has started to back fire and splutter when cruising and coming onto boost,regularly serviced and never missed a beat until now.very frustrating! any help much appreciated.

 

A little more information could help. Any mods, what has been repaired recently, anything unusual happen to the car before this started? So far I'd say check the tps first since that's a common place for problems like this to start.

 

And checking for error codes wouldn't hurt.