Is it possible to swap an 88 B2 EEC made for an auto trany to an 86 B2 EEC made for a standard? I switched my Auto trany for a standard trany from an 86 in my 88 B2. I was able to jerry rig the reverse light switch and neutral safety switch and taped the shift indicator wires. The standard is a FM145 with it's original transfer case.

 

I think going from auto to manual will work using the same ECU, but manual to auto, depending on which auto transmission, you'd have to swap ECUs because the A4LD requires the ECU to initiate the solenoids for upshifting / downshifting (?) I know there was a discussion in a previous thread about this. I personally would use the ECU for the type of transmission: Auto for an Auto trans, Manual for Manual. Not sure if there is some wiring harness issues or not, but that can be fixed if you have a complete donor vehicle (esp. if you go from manual to auto). I've been toying with swapping in a C-4 or C-5 into my 87, however, not sure either would do well without serious add-on cooling for the 33s or 35s I plan on putting on my rig after the axle swap and lift.

 

I'm sure it's possible (almost anything is possible given enough time, money, and human ingenuity). There were several differences (besides the differences between auto tranny vs. manual tranny) in the engine management systems of an '86 and an '88. For example, an '86 has and EGR system, an '88 doesn't. You'll need to get wiring diagrams for an '86 and an '88 and make sure that the computer will have all the necessary connections in the right places.

 

Thank you mr shorty. I wonder If I should trust Haynes or Chilton on the diagrams? I dont want to let the smoke out of the box by giving it 12 V on a pin where it should get less or the other way around. Also I think my 88 has an Exaust Gas Recirculator.

 

If you're certain it has an EGR system, then that's fine. It's always possible that you got an '88 model year truck built with some leftover parts from the '87 model year run. It may just complicate getting information (wiring diagrams and such) for your truck, because '88 officially didn't have an EGR system on it.

I don't know that I would trust Haynes/Chiltons for these wiring diagrams, though they might be good enough just to show whether or not the pin assignments are the same. To be sure, though, this is one case where I would probably run to the library and get good wiring diagrams from one of the professional repair manuals in their reference section.

 

Thanks, I think I will go to the library. I have found the real problem.... Stuped me, it was a cracked spark plug. But I should still get those vac lines hooked up. My MPG is about 14-16, is that bad.

 

Up until the rear end crapped out on my, mine was getting 18-22 mpg (lower end during the winter, higher end during the summer).

It seems that someone's always asking about mpg, so I know there are other threads where people have listed their "normal" mpg. You might try searching for them and compare what you're getting to others.