Runing Rich, WAY rich

[Ranger5.0]

when i swaped engines i replaced the ground straps and checked the harness grounds to be sure everything was in good shape. Me and the guys in the shop have been brainstorming over this for a while now, I will let ya know when we come up with a solid therory.

 

[mxracer652]

During start up & for 120-180 seconds afterwards (at that cold start up temp), the engine only looks at the incoming air temp, coolant temp, throttle position and maf signal.

If the ECT fails, it typically fails to the max cold reading it can give, -40*F (roughly -40C). I have seen this more than once.

For the engine to reach closed loop operation (general cruising, and pretty much everywhere except WOT), the coolant has to reach ~170*F (varies a bit between ECUs/models), so that would have explained your crappy gas mileage.

The IAC only controls your idle speed, it has absolutely nothing to do with the fuel.

The air charge temp isn't capable (iirc) of richening it up enough to sputter, it mainly pulls/adds timing.

A code 11 = system pass for key on/engine off, key on/engine on, continuous memory.

Have you changed anything non OEM from the donor? MAF/TB/injectors?

 

[Ranger5.0]

thanks for the info, but you mostly told me things im already aware of. Its speed density btw. I havent run a scan for a while now, but like two weeks ago it was passing everything even th oit ran like shat. Thats why im stil tryin to figure it out. Im tempted to replace the IAT.