I installed a ODB1 B16A SiR II engine from a 92 EG6 into my 90 Civic Hatchback Auto.
When I fist started it, the idle was a 3,500 RPM, I cleaned the IACV and FITV and it didn't fix the issue.
Checked ECU for codes and I got 5 and 7. Fixed the vacuum routing to the MAP sensor and it helped a bit, then adjusted TPS to 0.45 closed and 4.5 wot.
ECU codes went away but now it idles at 2,000 RPM

When I cover the upper hole inside the throttle body (IACV hole) idle normalizes,

1. Is it possible for the IACV to be bad without throwing an error code on the ECU?

2. Where can I get a replacement IACV for this motor?
IACV from ODB2 B16's and B18's are different, will the IACV from a delSol Vtec work?

Thanks in advanced for any help.

 

have you checked for other vacuum leaks. maybe your idle screw??? try that