...there are some possibilities...have to check one by one...but first u have MUT diagnosis at the Proton Centre..to confirm all the sensors (i.e TBS,TPS,ITS...etc) still functioning well...and from here you narrow down actual faulty...
usually its the throttle body...or yr timing too low...save fuel but no power & engine dies off easily....go get the workshop to check using pdt2000 or mutII
I guess this is my first post in this thread. I've change my Sei engine to 2.0 evo engine 3 months ago. All still standard. Just change the metal gasket.