Help Please- SR starts to misfire and stumble once hot...

[Cgeigert]

So I've had this one for over 6 months, I didn't do the swap. Car has: Greddy FMIC, Walbro, S15 T28, otherwise engine, ECU and fuel system is stock. Could use a CAS adjustment but otherwise has been running fine until recently with only a random misfire at idle. The only thing I changed recently was I added a TurboXS manual boost controller. So now when I drive when the engine is cold it idles, runs and boosts fine. After a few minutes once it gets to operating temp it starts to misfire at idle and won't hit boost, just stumbles if I try to WOT. The only other thing I've noticed is I smell unburnt gas more. This is what I've done so far...
-Bypassed MBC, no change
-Checked all connections and clamps, replaced a few vacuum hoses. All looked tight and felt tight
-Swapped MAF with my other SR, no change. I redid MAF harness wire and soldered and heat shrunk it.
-Checked injectors and coils, replaced plugs gapped at around .32

Problem is totally unchanged, nothing that I have done has affected the way the car runs. What should I do next?

[4cefed]

Could be a bad coolant temp sensor. If it's gone dead and stuck reading a cold engine, the management system won't adjust fuel and spark. Do you have a spare you could throw in for testing?

[Cgeigert]

I have two S13 with SR so if it is easily accessible I can switch between the cars. I'll search for that and check that next. Thanks for the reply. BTW, if that goes bad will it show on the temp gauge cuz mine is still reading normal.

[homeslicej2]

The motor has two different coolant sensors, one with a tab that sends signal to the dash gauge, and one with a plug that sends info to the ECU. 4cefed is talking about the one that sends info the ECU. They are both at the front of the intake mainfold b/t the head and throttle body.

[Cgeigert]

Yeah I got the ECU one. I was out of town for a few weeks so just getting started on it now. It really seems like a MAF issue because it just keeps hitting a wall around 3K or so and it tries to boost but just bucks. The only other thing I thought of that changed before the problem started was I redid one of the turbo ss lines they had on backward. The PO had removed the c clip for the actuator and swivelled it 180 degrees. So I redid it and swivelled it back to stock position. Does turning the actuator back and forth like that possibly damage the diaphragm?

[Cgeigert]

So I messed around a little and replaced some random bits just to rule them out. Igniter and Coils are good, MAF and MAF wiring is good. Quadruple checked all hoses and connections. It does it at all times now. Just hits a wall around 3-4K. Boost gauge readings are normal, no large vacuum and starts to stumble as soon as it tries to hit boost. Misfires alot at idle, seems to get worse once warm. From all I have read it really sounds like a MAF or loose connector type problem. Only other things I can think of to check are coolant temp. sensor, ECU, CAS and TPS, but I didn't think they would cause a problem like this. Car still drives ok as long as I keep it under 3K, just doesn't boost. Any suggestions?

[Cgeigert]

Just checked ecu codes and got a #12 MAF. I swapped the MAF with my other SR and it's definitely not the MAF, so it must be the wiring somewhere. Anybody know the colors of the MAF wires going into the ECU?

[Cgeigert]

Forget the MAF code, that was from when I unplugged it, I cleared ECU and getting a #55. So no codes. Checked fuel filter and pump. Even if TPS and CAS needed adjustment it shouldnt cause my symptoms. Don't have a clue what to do other than start throwing parts at it.

[Cgeigert]

No help? I don't know what else to do.