Do all Ranger engine computers use a gasket?

[Natedog]

Do all Ranger engine computers use a gasket where the big electrical plug bolts on?

I have two 87 Rangers and the 4x2 computer has a red silicone rubber gasket down in the plug part of the computer, its part number is: E7TF-12A650-F1A and has, "6HO81 Gasket" in the upper right hand corner of the label.

The 4x4 computer is part number E7TF-12A650-F1B and has, "7C163" in the upper right hand corner of the label.

These are both A4LD trucks...anybody know the difference between these two computers and if they should both have a gasket?

 

[Natedog]

Assembled the 4x4 computer without gasket and it works fine. But, does it matter? The pcb inside looks to be fully coated (sealed) with conformant coating, backside of wires can get wet, wires to pcb inside computer can get wet...so does the gasket do anything?

 

[MAKG]

'87s have the computer in the cab, so I wouldn't worry about corrosion or somesuch UNLESS you have a wet floor from a rust hole or leaky windshield, or you go through very deep water.

The different part numbers are probably different calibrations. It MIGHT make a difference when it comes time to get it sniffed. Since it runs, both the engines have the same number of cylinders. I suspect the difference is CA vs. Federal emissions. It's not technically legal to use a Federal emissions computer in a vehicle originally sold in California, but you'll probably get away with the other way around, as long as you can pass the sniff test. No one is going to inspect the label on your computer, but it may raise the emissions.

 

[Natedog]

It seems to have slightly more power than the other computer. So the "A" is CA and the "B" is federal or?

 

[MAKG]

I don't know what the calibrations are.

Especially for fuel injected engines, it ain't necessarily so that the CA one is emasculated. E.g., 1990 2.9Ls have a much better fuel management system (the only 2.9Ls with MAFs) for CA emissions than Federal.

Bad power MAY mean it's detonating. '87s have knock sensors, which will retard the timing. You can try disconnecting it and see what happens.

 

[Natedog]

Removed the computer and swapped the gasket in from the other computer just in case. All is well still.