# PCM identification **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [November 17, 2018, 8:59pm UTC](https://community.cartalk.com/t/pcm-identification/129034 "2018-11-17T20:59:43Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Jerad1389](https://avatars.discourse-cdn.com/v4/letter/j/9fc348/32.png) [@Jerad1389](https://community.cartalk.com/u/Jerad1389)\ **Post date:** [November 17, 2018, 8:59pm UTC](https://community.cartalk.com/t/pcm-identification/129034/1 "2018-11-17T20:59:43Z")
1987 Ford F150, 302, 5.0, v8, automatic. I’m probably going to have to replace the computer in my truck, and I haven’t pulled it out just yet. I was hoping to get a little information so I don’t order the incorrect one, since they are pre programmed. In my case, Advance Auto has several options. Is it as simple as finding the number on my PCM and choosing the matching one, according to the description? For example, Advance has options with “E7TF-AUA, AUB” and “E7TF-ATA, ATB”, among others. Does the original computer have those markings on it to match up, or is it more complex than that? I’m not able to pull the computer out and check yet (at a relative’s house, out of town). Any help would be greatly appreciated, since these can’t be returned after purchased ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [November 17, 2018, 9:05pm UTC](https://community.cartalk.com/t/pcm-identification/129034/2 "2018-11-17T21:05:42Z")
Every computer I’ve replaced was with a used one from an auto recycler. All I had to do was bring the old one with me so they could match up numbers/bar code. Tester ---
**Author:** ![asemaster](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@asemaster](https://community.cartalk.com/u/asemaster)\ **Post date:** [November 18, 2018, 12:41am UTC](https://community.cartalk.com/t/pcm-identification/129034/3 "2018-11-18T00:41:39Z")
You can figure out which ECM you need either by matching the number on your original one or by cataloging by specifications. There should be options in the catalog for which engine size, manual or automatic, CA or Federal emissions, and possibly gross vehicle weight. The original ECM will have the numbers on it but you will have to remove it to see them. The first four characters will be production numbers, the middle five characters will be 12A650, the last 2 or 3 characters will be calibration updates. You can go forward on the last 2 or 3 characters, but not backwards. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [November 18, 2018, 6:58am UTC](https://community.cartalk.com/t/pcm-identification/129034/4 "2018-11-18T06:58:18Z")
All I have done is Buick and like Tester said just get a used one. They rarely are bad. On mine you just match the numbers on the tag but the prom is exchanged from the original to the new one. No idea how Ford does it though but should be evident when you look at it. ---
**Author:** ![Jerad1389](https://avatars.discourse-cdn.com/v4/letter/j/9fc348/32.png) [@Jerad1389](https://community.cartalk.com/u/Jerad1389)\ **Post date:** [November 25, 2018, 1:38pm UTC](https://community.cartalk.com/t/pcm-identification/129034/5 "2018-11-25T13:38:39Z")
I’ve finally got the correct computer and swapped it. Now it won’t start… It just cranks. ---
**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\ **Post date:** [November 25, 2018, 2:27pm UTC](https://community.cartalk.com/t/pcm-identification/129034/6 "2018-11-25T14:27:49Z")
Was it doing that before you swapped computers? What was it that led you to think you needed a new computer? Twice in my lifetime I have had a mechanic diagnose my problem as a bad computer and both times they were wrong. ---
**Author:** ![Jerad1389](https://avatars.discourse-cdn.com/v4/letter/j/9fc348/32.png) [@Jerad1389](https://community.cartalk.com/u/Jerad1389)\ **Post date:** [November 25, 2018, 4:20pm UTC](https://community.cartalk.com/t/pcm-identification/129034/7 "2018-11-25T16:20:43Z")
It has done it a few times, but I’ve replaced the starter and solenoid very recently. The reason for switching the computer was to (hopefully) fix it from stalling while driving. I did relocate the ignition module, so I’m wondering if I don’t have the ignition timing correct? It’s been sitting a lot for the past 6 months too, due to the stalling and lack of time to work on it