E36 IAC?

I got a known good MAF, needless to say, this is not the issue. I ran a compression test on the vehicle. Here’s the numbers:

CYL # 1 - 200psi
CYL # 2 - 195
CYL # 3 - 190
CYL # 4 - 165
CYL # 5 - 200
CYL # 6 - 205

My Bentley manual states that the minimum 142-156psi, so I have no clue whats going on here. The head was replaced, prior to me getting this car. I have no clue what vehicle it came off of. It also appears that it was never run trough a machine shop prior to the install. I’m seriously thinking about swapping out this engine for a 328 right about now. I’m going to pull the front O2 sensor and take it for a ride when the weather clears up. Hopefully this will tell me if it’s a clogged cat or not.