Is it possible to compression test engine while the uim is disconnected?

 

Yes

 

one question,
does oil affect compression testing?
if so, does having the metal rod from the metering oil pump disconnected from the throttle body affect compression?

 

Yes and it will kill your engine after not too long.

 

I will have to say, I ran mine with that bar disconnected *first rotary, didn't know wtf that bar was for, and when I bought it, it was just dangling there....*and I ran it like that for months, and amazingly, the car is still running :O

 

Without some oil on the seals compression falls off dramatically.
Also compression varies a lot with cranking speed.

If you're not sure if the MOP is working then premix some TC3 or MMO with the gas.