i have a 1994 civic with a obd1 p28 ecu chipped with hondata, on a b20 with an ls intake manifold and transmission, and skunk2 70mm throttle body. those are my only mods onto the motor i have done. i got the car to start today after a while of working on it and it idles rough/idle surges if i’m not mistaken. i’m not getting any codes thrown on the hondata interface. although the check engine light was flashing when i attempted to start it up, when it started it ran perfect for a second then flashed the CEL again like it did and i shut the car off. i felt the header pipes and cylinder 1, 2, and 4 were warm and 3 was cold. i think it could be a valve but i’m not sure. i did a compression test in the motor before installed it so i’m not really sure at this point. Thanks to anyone in advance i’m just stuck at this point and no one seems to have this issue

 

What were your compression test numbers ? What codes are stored in the ECU ? Big throttle bodies are notorious for causing idle issues including a "hunting idle", so if you still have the stock one, I suggest you put that one back on and shelf the 70mm T/B.