Power Loss / High idle

[DieselDano]

Good Morning All,

I hope someone here can maybe help me out.

I have a Mustang that has a full 1996 Explorer Engine / Harness swap. For all intents and purposes, it's a 1996 Explorer.

I got the car running this past weekend, but I have some drivability issues.

First off, I have no codes. Idle stays high, around 2500. Ift will also cause the headers to glow if left idling for a few minutes. If I disconnect the MAF, it will idle down and doesn't seem to get the headers to glow. However, on the road with the MAF connected or not, it will run great, then fall on its face. Foot off the throttle, you'll get acceleration, then it will fall on its face again. I can't drive it like this.

Everything is new, I just rebuilt the internals. New o2s, IAC, cam and crank sensors are new too.

Please, any advice is welcome. I'm at my wit's end.

Thanks!

 

[bigred4x4]

I swapped a 95 4.0 into a 96 and because of pigtail on iac was different but still connect the computer had gotten damaged dealer ship couldn't figure it out neither could I so I took it to a mustang shop and they found the problem but it idled crazy and didn't want to go below 1000 rpm while coming to a stop which eventually caused an accident so computers are funny when you start doing engine swaps and the motor isn't an exact match I'd start with the computer and go from there