horrible idle, no boost

[1991black240sx]

so about a month ago i bought a 89 hatch with a ca swap. the pro was the is was a flordia car (i'm in wisconsin) no a spot of rust. now the con, the car was not running. i had it home for two days and i got it running, it wasn't running very good. still isn't. i know the timing belt placement is correct and the CAS is in the correct place. still idling very ruff and not building boost. also when the car warms all the way to normal opperating temperature it starts to miss fire. it has a gt28r, external wastegate and front mount. only major mods. ( don't ask why they put an external wastegate onto a stock internal wastegated turbo, i have no idea)

anyone have any ideas?


good compression
good fuel pressure
no shaft play on turbo

[boost_boy]

so about a month ago i bought a 89 hatch with a ca swap. the pro was the is was a flordia car (i'm in wisconsin) no a spot of rust. now the con, the car was not running. i had it home for two days and i got it running, it wasn't running very good. still isn't. i know the timing belt placement is correct and the CAS is in the correct place. still idling very ruff and not building boost. also when the car warms all the way to normal opperating temperature it starts to miss fire. it has a gt28r, external wastegate and front mount. only major mods. ( don't ask why they put an external wastegate onto a stock internal wastegated turbo, i have no idea)

anyone have any ideas?


good compression
good fuel pressure
no shaft play on turbo

If you're engine is not building boost, then you have a major leak. And I would start around this bootleg external wastegate the previous owner added. Hard to really give you solid advice as you dove into a mess to start with.

[1991black240sx]

well it is a synapse synchrnoic wastegate. should i double check all the intercooler piping? it is like the wastegate is opening up immediately.

[boost_boy]

well it is a synapse synchrnoic wastegate. should i double check all the intercooler piping? it is like the wastegate is opening up immediately.

So the turbo still has the actuator attached to it? Do you have any pictures of this monstrosity? I would dump the synapse and put it back to stock and definitely triple check piping and everything for leaks, loose connections and don't forget to check the trouble codes on the ecu.

[1991black240sx]

the actuator is not there. how do you check the trouble codes on the ecu. i will take pics today of this mess.

[sjbsuperman1425]

to check for trouble codes, hit up the FSM in the EF & EC section. It'll tell you how to read codes and what the codes mean.

[1991black240sx]

sorry for such a long time between posts, been working a lot. so i think i have a Z32 MAFS. could that be causing the unsteady idle? i got the boosting issue fixed. the only way i can get it to hold a flat and steady idle is with a hand over the open mafs. i bought an adapter plate and filter (yes from ebay lol) the holes don't line up, that is why i am thinking that i have a z32 mafs.

[1991black240sx]

i just order a stock ka-e mafs for 25 dollars. i am going to see if that fixes everything.