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FE Power Forums => Non-FE Discussion Forum => Topic started by: cleandan on November 16, 2020, 11:06:23 PM

Title: 1989 F150 ECU questions.
Post by: cleandan on November 16, 2020, 11:06:23 PM
Hello all.
I am working on a 1989 F150, 2WD, 300-I6 (EFI), 5spd manual.
The ECU is giving intermittent troubles and I have removed it for testing and identification.

The problem lies in my lack of technical knowledge concerning replacement ECU's.
Everything I read tells me the ID#'s are critical in getting the right programming for the ECU.

My ECU ID#: E8TF-12A650-X2B

Neither I, nor the autoparts stores, nor places like Rockauto and others, lists this exact part number.
None of the places has the ability to tell me if there have been superceded part numbers taking place over my older number...No cross references either.

Does anyone know where I can get a proper ECU?
Does anyone know if there is a different ECU ID# that will work with my engine combo?

Thnks for any and all help.
Title: Re: 1989 F150 ECU questions.
Post by: jmlay on November 17, 2020, 12:11:32 AM
I would imagine the hardware is somewhat generic in nature to some extent. Ford would likely have a few hardware versions that were shared with multiple vehicles and simply flashed with the appropriate stratagem and date tables for a give car.  There are several companies that specialize in the used/remanufactured market. A reputable company will ask for the vin to validate a replacement. Here is a quick google search that will provide you some options:

https://www.google.com/search?q=E8TF-12A650-X2B&rlz=1CDGOYI_enUS843US843&hl=en-US&sourceid=chrome-mobile&ie=UTF-8
Title: Re: 1989 F150 ECU questions.
Post by: WConley on November 17, 2020, 12:14:30 AM
A quick Google search produced this hit on your ECU calibration - in stock:

https://www.fs1inc.com/e8tf-12a650-x2b-1988-ford-truck-f-series-4-9l-engine-computer-pcm-ecm-ecu-plug-play-efi-sd20a.html
Title: Re: 1989 F150 ECU questions.
Post by: shady on November 17, 2020, 07:58:26 AM
Make sure you don't have harness problems. Ford in their infinite wisdom made some important connectors under the hood non weather sealed. Makes for intermittent head aches for sure.
Title: Re: 1989 F150 ECU questions.
Post by: cleandan on November 17, 2020, 08:46:09 AM
A quick Google search produced this hit on your ECU calibration - in stock:

https://www.fs1inc.com/e8tf-12a650-x2b-1988-ford-truck-f-series-4-9l-engine-computer-pcm-ecm-ecu-plug-play-efi-sd20a.html
Thanks. I was literally on that site and was unable to bring up my exact ID#
I typed it into the search a couple times just to make sure I did not fat finger the numbers too.
I did find a few numbers that were very close, such as XB, but without the 2 inbetween.
I also typed in caps for the letters of the part number, maybe that makes a difference.
Title: Re: 1989 F150 ECU questions.
Post by: BattlestarGalactic on November 18, 2020, 03:30:08 PM
I went through this with my previous 89 F150/302/AOD truck.  I got mine from Autozone, though it really didn't help with much.  In the end, I put a carb'd roller cam 302 in the truck and eliminated the computer issues.  This goes back 6? yrs ago.
Title: Re: 1989 F150 ECU questions.
Post by: Stangman on November 18, 2020, 09:08:33 PM
Thats cheating Larry.  ;)
Title: Re: 1989 F150 ECU questions.
Post by: BattlestarGalactic on November 19, 2020, 07:37:00 AM
Ya, but I was tired of dealing with little nuances of that computer.  I did lots of reading on sites and just said "screw it".  Friend had a nice running stock roller motor, stuck a 600 Holley on it and presto chango no more computer to deal with.  I also swapped in a 5 spd also because of the AOD was starting to act up at 175K miles.
Title: Re: 1989 F150 ECU questions.
Post by: My427stang on November 19, 2020, 07:44:10 AM
If you are willing to roll the dice a little, I would go to Advance Auto online, go with your specific application (year, engine, tranny, etc) and buy one, might have to join their club, but they are about 113 and you can use COUPON25 for a 25% discount.  90 dollar gamble or so with tax, but they may even take it back if you just hang it there and tell them when you got to the truck it was the wrong part number.

I have a hard time finding the suffix yours has too, but I'd be hard pressed to pay the bigger price too.
Title: Re: 1989 F150 ECU questions.
Post by: babybolt on November 19, 2020, 08:40:47 PM
Those 80's to 97 trucks get a lot of water running down the windshield into the hood to cowl gap where it goes into a plastic rain gutter on the firewall - and on the driver's side the water dumps right onto wiring harness.
Title: Re: 1989 F150 ECU questions.
Post by: cleandan on November 20, 2020, 06:11:08 PM
I did some searching. I talked with my parts store manager. He talked with his Ford delaership mechanic he confides in.
They searched up and down with my VIN# as well as other useful information taken directly off the ECU tag.
The "trouble" part of my numbers lies in the (x2b) portion, all else is verifiable.

The best info we can come up with is the aftermarket boxes have simply done away with the number suffix between the two letters.

I have a box coming with the (xb) numbers and I will find out how this goes.
My manager friend said I could return it if it does not work properly.

In a holding pattern for the next few days for the box to arrive.

Yes, I agree with the water intrusion part.
The multi-pin connector does have a nice silicone seal across all the pins, but the rest of the connector is pretty exposed. I may devise a deflector of some type to help with this...Or just leave it and fill the area with dielectric grease and hope for the best.
None of the pins or connector is corroded at this point, which I found surprising.
Title: Re: 1989 F150 ECU questions.
Post by: My427stang on November 20, 2020, 07:51:34 PM
Although corrosion can be a problem, all the failures I have seen are from age and capacitors burning up everything around them

Here is my A9L (in my car, but 93 5.0) I replaced it with an Autozone and just plugged my rider chip into it.

(https://i.postimg.cc/X7hkz6hx/Board-Arrows.jpg)
Title: Re: 1989 F150 ECU questions.
Post by: cleandan on November 23, 2020, 11:05:54 AM
This is something I have suspected.
I have not bothered to open and electrically inspect the ECU...but, most capacitors do eventually fail. Resistors can last seemingly forever in many instances, but not the capacitors.

The capacitors have been the trouble in almost every instance in my vintage audio gear too.
Title: Re: 1989 F150 ECU questions.
Post by: shady on November 23, 2020, 05:11:26 PM
This is something I have suspected.
I have not bothered to open and electrically inspect the ECU...but, most capacitors do eventually fail. Resistors can last seemingly forever in many instances, but not the capacitors.

The capacitors have been the trouble in almost every instance in my vintage audio gear too.

The capacitors have been replaced under the chassis. The cans are empty and just for show. This amp is a 1952 Bogen 2 channel mono that I converted to stereo. Almost every flat screen TV that quits is because of under rated caps (cheap) in the power supply.
Title: Re: 1989 F150 ECU questions.
Post by: cleandan on December 04, 2020, 09:21:16 AM
I finally received the new, rebuilt, ECU.
Installed the part and the truck runs very well, without any hickups, like before.

I just hope it lasts more than one year, like so many other aftermarket/replacement parts.

Thanks for all the good input for this situation.

Have a great day.
Title: Re: 1989 F150 ECU questions.
Post by: chris401 on December 06, 2020, 09:54:01 PM
I finally received the new, rebuilt, ECU.
Installed the part and the truck runs very well, without any hickups, like before.

I just hope it lasts more than one year, like so many other aftermarket/replacement parts.

Thanks for all the good input for this situation.

Have a great day.
If you have a scanner (not a simple code reader) you can see the pid values the computer sees and produces. It is a good habbit to go through the tedious task of checking the grounds related to your problem. I was ready to replace one on an early 1996 F-250 when I discovered the ground signal to the EGR position sensor only worked when I unplugged it and bent it up to test with a meter. It is not often an ecu goes bad but possible. I would say Ford's 4 and 5 systems are more likely to quit switching a ground signal before other makes. The MaxiSys MS906 BT is a decent machine and not super expensive. It will come with the Ford connector and other common early adapters. Even one for your Maxima. Do you still have that car?
Title: Re: 1989 F150 ECU questions.
Post by: cleandan on December 06, 2020, 10:19:34 PM
Thanks for the information.
I never had a Maxima. You must be thinking of another person.
Title: Re: 1989 F150 ECU questions.
Post by: chris401 on December 07, 2020, 10:59:33 AM
Thanks for the information.
I never had a Maxima. You must be thinking of another person.
Ok, someone on this board was having problems with a modified Nissan.
Title: Re: 1989 F150 ECU questions.
Post by: BattlestarGalactic on December 08, 2020, 09:47:38 AM
I remember, though can't say who it was either.
Title: Re: 1989 F150 ECU questions.
Post by: chris401 on December 08, 2020, 07:13:49 PM
Thanks for the information.
I never had a Maxima. You must be thinking of another person.
It was the other guy on the other forum. https://www.fordfe.com/viewtopic.php?f=74182&t=113027&p=1061795&hilit=Nissan#p1061795