Got a 91 f-150 4x2 5.0 E40D

put a new engine and trans into this truck. Got it running but not smooth. Have a horrible idle issue that I can’t seam to find. Put all new sensor in it, good fuel pressure, good vacuum. Have code 55 and 56.

can’t figure this out and help if greatful

 

New MAP sensor? No vacuum leaks?

 

Yes new map sensor. Wire harness have 5v reference going to it and good out put signal. And holding at 32in of vacuum at idle.

 

IAC maybe?

 

32 inches vacuum is not possible. Normal is around 20 at idle.

 

My apologies when I wrote 32 I felt like it was wrong checked it and it’s at 23in

 

iac is good can send power to it and hear a noticeable difference to engine