Hi guys

I bought a EG6 SiR a while ago with a b16a2 in it. When I would put the foot down if felt like it was holding back a bit, like lagging. I didnt mind because I was buying another engine anyway. I have now finished putting a b18cR in it and it feels like the same thing!! though now im getting CEL 14 IAC (EACV) - idle air control valve. Have tried to find a break in the loom (found none) checked the plug its fine. Iv also changed the IAC with 3 others and still getting the code. Could this be a buggered ECU and is what is causing the "lag"

(Using a p72 ECU (same ECU that was being used on the old engine)
HELP!

 

This is a remote guess but... I am thinking you may have your two wire iacv/egr/iat sensors mixed up. You may also have a burnt IAT sensor due to this.

Check/test your iat sensor & also resolve all of your MILs by determining what plug is supposed to go to what sensor etc.

Also, the p72 ecu is not exactly the ecu you should be using with a b18cR engine.
You should have the p72 ecu chipped for the b18cR engine or you should buy a pre-chipped obd1 p28 spec ecu mapped for the b18cR engine.

Remember, not all "chips" are the same. Some people go out and try to save $50 by buying their homeboys chipped ecu from ebay & end up spending twice as much in the end.