Hello all, I have a 1988 F150 4.9l w/ 4 speed (T-18). I am pretty sure my ECM is bad and have been looking around for another one. My ECM has the following numbers.

EEC-IV EFI 5D20a 32K PROM
E8TF-12A650-CL2A G
6EC2850F33 10294 320
(Then, in very large font, it has.... "8TT" on the far right with "8E06" underneath the "8TT"


I wanted to make sure the ECM I have is the correct one for my application as this truck has 400,000 + miles on it and I'm not sure if it has been replaced before. Is there somewhere one can go to learn what the numbers mean?

Someone told me that the numbers that REALLY matter are the 5D20a and the CL2A, but they were not sure what they mean either. Called a few vendors and they said if my truck was newer they could go by the VIN but that mine was too old to show up in their software.... Story of my life.... Most of the ECM's that are available are for V8 engined automatics, which I have the opposite end of the spectrum. Any help would be most welcome

 

5D20a is the hardware inside the computer which can run different program codes. 8TT is the vehicle specific program code running on this hardware. E8TF-12A650-CL2A is the ford part number for this hardware and software combination.
I also found one of these on eBay right now by searching Google for your E8TF-12A650-CL2A number. Ad has a list of compatible vehicles.
Hope this helps.
William

 

Thanks William! Very interesting information. I have found a couple on Ebay as well but I don't want to buy one until I'm sure what is correct for my truck. Thanks again

 

Also, what is confusing is there are a couple of "CL2A" ECM's on Ebay that say they are for an automatic equipped truck. So, I'm wondering if mine was replaced at some point with the wrong one....

 

The early automatic transmissions(C4,C6,AOD) were not computer controlled so the PCM is nearly identical in operation to one for a manual transmission so it can be used in your truck with a manual trans.

 

Thanks for the information Paul!