Hattig43

I have a 302 motor I took out of a 93 And put it in my 94 that had a maf sensor in it. I used the original wiring from the 93 motor and it runs I do get some idle problems will drop from say 1100 rpm to 400 in a matter of seconds.
I dont know the differences I'm assuming the idle problem is because i put a sd in a maf truck. I've been driving it for a few months now and hasn't really been an issue it never stalls on me but recently my gas mileage has tanked badly I was wondering if the maf had anything to do with this? My o2 sensor also may have been welded to my headers and I know that's part of the problem but in my other trucks when that sensor goes out the mileage has never been this bad.

For reference
the 93 f150 had a 302 with the Aod so I did not swap computer's

the 94 had a 302 out of an 89 f150 with an e4od And I don't recall if it had the same problem but I know it had a slight issue with idle.

Also want to add that I originally used the harness off the 89 motor with the maf setup and it just flooded the newer motor.

basically asking if I need to do a full maf conversion if so what do i need or should I stay SD I just want better mileage not sure this is the cause but filled up yesterday morning and now I'm on empty.

Shagg

Which ECU are you using?

Hattig43

I'm using the one from the 94 that had the maf in it because the 93 motor's computer Had an aod not e4od so i did not think they were compatible.
I would imagine that could cause some problems but I was not 100% sure if it could be from somewhere else hence why I made the post

Shagg

Then I would start by switching the '94 harness back onto the motor.

sswari

The reason being is that the MAF harness will be able to do the sequential firing of the injectors, as well as the There may be other pins relocated between the 2 that the ECM needs.