Alright trying to get my GSR Swapped rex running perfect. Have alot of issues when I change out the ecu

Now running factory P72 GSR ODB1 ECU. Car stumbles a little at 3-4K RPM under light throttle, goes away when I go more then 1/4 throttle. Codes for VTEC (21) Injector (16) and O2 (41)

Have a chipped P28 ecu, GSR map program running crome. No codes. But stumbbles badly at any rpm and any throttle.

Factory unchipped P28, stumbbles to 4K then runs fine. Codes for Injector and vtec.

Chipped P72, no codes most of the time, but everyso often throws Injector, and vtec


Do you think all the stumbling at low RPM could be an injector going out? They all measure the right impedance (Low impedance Injectors) and box has been switched out.

Car is 88 CRX, ODB1 GSR with Boomslang swap harness.

 

anyone any tips?

Some people think its a bad injector....cause I am having possible injector issues....when I lightly throttle it, it will hessitate/ bog...they think the chipped ecu is making it worse