89 that scans as 86?
Thread Starter
Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
89 that scans as 86?
Hey guys, I will try to keep this short. I have a 1989 L98 Auto., car runs just fine after several years of working and replacing many parts. This is more of just still trying to learn about ECM's than a repair. I have a Actron scanner with the GM cartridge that works just fine for my cars. On this tool the year,model, and engine specifics have to be entered. If I enter 1989 (which it is), I get a error reading. I have to enter it as a 1986 in order for tool to read any codes or data. Tool does work as it shoul as I have owned it for 10 years and use on several other cars with OBD1. So,,,,? could it have the wrong PROM and/or the "service replacement" ECM? I know that when a ECM is replaced the PROM is usually kept from the old ECM and installed into new one. Correct? Any words of wisdom I would greatly appreciate. Thank you.
Joel
Joel
Instructor
Joined: Aug 2007
Posts: 230
Likes: 1
From: Covington GA
Whether the person doing the replacement pulls the EPROM is going to depend on who was responsible. There's probably a lot of backyard mechanics (and quite likely some professionals too) who, if they conclude the ECM is bad, would just go to a junkyard, get another one, and just plug it in without opening the box. I think someone's done that to your car.
Melting Slicks
Joined: Aug 2003
Posts: 3,403
Likes: 398
From: Lakeville MI
In addition to checking the label on the eprom, your scan tool should be able to read and display the prom id.
That should tell you which bin file is programmed if it can be identified (and hasn't been modified by somebody).
Read the prom id and post it here. Maybe someone can id it for you.
That should tell you which bin file is programmed if it can be identified (and hasn't been modified by somebody).
Read the prom id and post it here. Maybe someone can id it for you.
Pro
Joined: Oct 2004
Posts: 504
Likes: 82
From: Melbourne Victoria
Thread Starter
Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
Thanks for all the replies. Should I even be concerned about this issue? Car runs and drives very well. Looks to me like the 86 and 89 all have same MAF, MAT, etc. Not sure of any difference in fuel pump pressure or spark timing. Only problem I have as we speak is the MAT reading is a constant 392 degres. But it has been like this for a long time, just keep forgetting to repair. Doing that now.
Joel
Joel
Thread Starter
Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
I finally got some to remove the ECM and check the numbers. On the ECM it has a label: Reman. by GM corp Service Part #16198445. On the Prom it has #APKC 1304. Does this look correct. Thanks
Joel
Joel
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