Would someone in brief explain what is a OBD2,I have a 94 f250 with a 7.5 with mfi.I know what efi is,just not the obd2.which is the better system.Thanks

 

In a nutshell;

Two separate things OBD & EFI.

MFI is version of EFI.

OBD2 is a technology upgrade from OBD1.

EFI Evolution > CFI > MFI > SFI

https://en.wikipedia.org/wiki/On-board_diagnostics

https://www.cars.com/articles/what-a...1420690418419/

 

94 f250 with a 7.5 > OBD1 I believe.....

 

vjsimone,thanks I read both articles,the answer was right in front of my face all along.

 

Yep, definitely OBD1. My 1997 w/460 is OBD 1. Only the Cali models in 96/97 got OBD 2

 

My truck came from new mexico,94, f250, xlt ,ext. cab, 4x4, 8800 gvw, 8ft bed

 

and a e40d tranny

 

The twist on the Ford MFI is that, electronically, it is 2 banks of 4 injectors on your V8, 4 injectors energize at the same time, then the other 4. Fuel hangs around in the intake until it is sucked into the cylinder.

As the link stated, the move to SFI improved the efficiency....

 

Is this something that is a have way easy swap over?

 

Don't swap anything. Learn to diagnose and test without hurting anything.

Did your truck come from New Mexico, the state, or from Mexico, Maine?

Sequential injection is theoretically more efficient but you can't measure it at the gas pump.

 

It was bought new in new mexico state,I bought it 2yrs ago.I put it up every winter,and it was never driven in snow just used in summer.I live just north of mexico maine

 

MFI is more commonly referred to as "bank fire" injection.

 

You just missed me, i would have stopped in... I spent Thursday night in Lewiston, on me way to Newfoundland....

 

MFI actually stands for Multi-point Fuel Injection, it simply signifies that the system uses separate injectors for each cylinder versus the carb style TBI(Throttle Body Injection).

Bank fire injection is actually a misinterpretation of what really happens. The injectors in the SD(speed density) EFI system most common on these trucks fires the injectors in batches of 4 but those batches are not simply left and right, 2 injectors from Bank1 and two from Bank2 are in each group.

SD(speed density) EFI is a system the uses manifold vacuum to determine engine load.

MAF(Mass Air Flow) EFI uses a meter in the intake air duct to measure airflow through the motor in real time to determine engine load. On these Ford trucks that system also includes SEFI(Sequential EFI) where each injector is fired individually following the firing order.

 

Thanks to all of you for putting the record straight.