rx-7 obsessed

hey guys need some help again. 86 GXL swap to a t2 still the s4. It has the typical signs over over boost. the two things i find odd are, 1 its all stock with 36k on a new motor, and 2 i tested everything via the FSM and it was all good. So at around 5500 rpm in 3rd at WOT it feels like i just hit a brick wall. The car just jerks and looses all power, it feels sort of like detonation but not really. the even stranger thing is that no mods have ever been done to this motor. Also all lines are brand new as well as a fuel pressure check has been done and came back in spec compared to the FSM. And finally yes i did check the compression its all good 115 at all seals. So after that very long write up my question is what can i do? I have absolutely NO clue what to check next??? TPS is adjusted properly as well!

KhanArtisT

iTrader: (2)

No boost gauge? Remove the line for the MAP and plug it, go for an easy drive and try to duplicate the problem but be careful.

dawicka2

my s4 t2 swap did that same thing before the afm completely **** the bed. I could not find the issue for the life of me until it quit while i was driving it. Swapped afm.... fixed and no worries.

car was never right after i swapped in the t2 engine. my issue was it also stumbled in the 6k range. new afm took care of that problem completely.

john ny

rx-7 obsessed

^^ that sucks i just swapped that damn thing. just another update that i missed in my write up my boost gauge goes higher in 1st and 2nd then it does in 3rd but yet it will only do this in 3rd gear? im running the stupid stock one but it looks like it works pretty good. i am positive the +40 is 6 psi. i also just checked my AFM according to the FSM and its fine. no dead spots or anything?

rx-7 obsessed

ok i swapped my AFM out for another one out of another turbo that ran strong, still have the same result? anyone have another suggestion

rx-7 obsessed

bump because i don't want to blow my car up

Turbonut

iTrader: (1)

Just a thought, did you upgrade the fuel pump and is it geting the 12 volts under acceleration?

rx-7 obsessed

stock fuel pump from t2 and yes it has 12.14 volts.