engine control module question

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engine control module question

doni10
hello people,

am trying to get my head around all thats under the hood with 1981 truck, the 'control module' doesnt seem to be in the best of shape? can anyone tell me if something is meant to plug into the top of it? looks like it might be the case?
also lastly, next to it there seems to be some sort of 'heat sink', -(as seen in the corner of picture 1), that doesnt appear to be connect to anything...
have seen others of these in other peoples trucks online. would anyone please be son kind as to illuminate me on whats up with this!!

thank you so much.


1981 F-250 camper, 4.9l inline 6, RWD
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Re: engine control module question

Gary Lewis
Administrator
Doni - That is very curious.  Weird even.  As said, I don't think Ford put computers on the 1981 trucks, but you have one.  How 'bout moving the black wire and getting me a good pic of the part number on that thing?  I can probably tell you from whence it came.

As for the heat sink, that might be several things.  One is somebody's home grown battery isolator.  I made one similar to that for my '72 F250, and it allowed the alternator to charge two batteries at the same time.  Maybe get a better pic of it?

And below the MCU is the ignition module.  Specifically a DuraSpark-II unit as I can see the blue grommet that the wires are coming out of.  And, if you have a DS-II ignition you don't have an MCU/computer.  
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: engine control module question

Frank Wyatt
I found this https://www.ford-trucks.com/forums/1473973-1983-f-150-microcomputer-control-unit.html on another site that appears similar. I'm not sure if that was original to your truck though but it appears to be bypassed with the DS II blue grommet module. That appears to be meant to be a piggy back system that I never seen before but California had some unique set ups due to having to find fast solutions due to emission requirements at that time. I'm not familiar with the Califronia ignition set ups or the exported vehicles though. The truck in that post was an '83 F 150 so that is curious as yours is a 1983. On the blue thing I agree with Gary as that could be a battery isolator of some type for dual batteries as it looks like one that I have that I'm not using right now, it's not blue though.
1981 F 150 Custom 300 ci with a fully rebuilt 1968 240 head Carter YFA T-18 3.25 9" rear 2WD
dual gas tanks
1990 Lincoln Town Car 5.0 AOD
Home town Mc Kenzie, TN
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Re: engine control module question

Gary Lewis
Administrator
Frank - His intro thread says it is a 1981, which is why I'm confused as I didn't think any 81's came with a computer.

However, I was wrong!    The 4.9L for California did have the computer, as shown below, which is a page from the 1981 EVTM here: Documentation/Electrical/EVTM/1981 EVTM/Feedback Carb Control.

So I'd bet that his is a CA-spec and someone has neutered the computer and installed the DS-II module.  I asked to see the certification label thinking that might tell, but the best bet would be to find the calibration code on a label on the engine, as explained here.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: engine control module question

Gary Lewis
Administrator
Doni - With the discovery explained above, I think you may well have the right carburetor.  Not that you want to keep it, but that may be the one that came on that truck.  If it was me I'd want a carb off an earlier truck that didn't have the emissions controls.

One of our members, 1986F150Six, has just such a carb on his truck, and it is a Carter YF 4901 S carburetor from a 1970 F350 with 300 engine.  It works very well on his truck, which has been proven by the excellent MPG he gets.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: engine control module question

doni10
This post was updated on .
Gary and Frank thank you so much for your inputs.
Little by little the truck, and its thousands of wires, (- think 40 years with multiple owners, motorhome electrics, thousands of yards of insulating tape and lpg paraphernalia thrown in to boot!) is beginning to make more sense.




was trying to see where all the now obsolete wires might be, and i managed to find these connections hidden behind the glovebox, im hoping that the two unused ones were once occupied by the control module. - as opposed to something else i might actually need now :)




i'm in agreement with you gary and actually have just ordered a replacement carb, not sure exactly which year it is but it seems to be free of the emissions stuff.
as far as de-california-ing of the engine goes. im sure there's a load of info around here on the subject.,,,
will get to it!

also, that heat sink thing almost certainly was/is a battery isolator as the leisure battery sits next to it!
excellent work

thanks so much again.



1981 F-250 camper, 4.9l inline 6, RWD
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Re: engine control module question

Gary Lewis
Administrator
Doni - The number on the MCU proves that your truck was surely built to meet California emissions standards.  I found several hits on that # E1TF 12A651—C1A, C2A.  (By the way, in Fordspeak, any number on a part is not a part number.  Instead it is an ID or engineering #.)  I got lucky and found that number in the Master Parts Catalog in the calibration parts lists for several 1981 trucks, but the list below is probably the one that fits your truck.

Note that this list is for Calibration No. 1-52S-RO.  That's the "calibration code" and you might actually have a label on the valve/tappet cover with that number.

As for the connectors in your pic, they are probably for things like the courtesy lights, door locks, etc.  And there's no other module except that MCU.  You can remove that and anything it is connected to as it cannot be working with the connector to the carb unplugged.

Luckily the early systems like that were standalone.  So you can trace the wires from the MCU and remove whatever they are connected to.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: engine control module question

Frank Wyatt
That's my thinking as well, removing the now unused MCU and associated parts and cleaning up the under hood wiring. It will look neater, making diagnosing any other issues easier, and eliminate the look of being jerry rigged together.
1981 F 150 Custom 300 ci with a fully rebuilt 1968 240 head Carter YFA T-18 3.25 9" rear 2WD
dual gas tanks
1990 Lincoln Town Car 5.0 AOD
Home town Mc Kenzie, TN
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Re: engine control module question

salans7
I initially thought this was a California spec truck but did not want to speak under uncertainty. But I vaguely remember from the Eff Tee Wee days that 1980 was the last year for non-computer control in California and that 1981 brought the MCU, although I wasn't sure where it was placed. My old 1980 was a California spec truck, and all it had was at least 20 different vacuum lines going everywhere you could put one.