ECM Munbers
Thread Starter
Instructor
Joined: Nov 2018
Posts: 113
Likes: 4
ECM Munbers
Hi,
I have an 1986 Convertible that may need a new ECM. I found one that has the same service numbers on it. Is that all I need to make the Match? Mine has another code on it AANM, Do both of them have to have that on them too, or is the service code enough?
Thanks,
Jim
I have an 1986 Convertible that may need a new ECM. I found one that has the same service numbers on it. Is that all I need to make the Match? Mine has another code on it AANM, Do both of them have to have that on them too, or is the service code enough?
Thanks,
Jim
Pro
Joined: Feb 2009
Posts: 655
Likes: 164
From: Vancouver Washington
Smitty,
I have an 86 vert and I can get you the numbers. I'm at work right now and can't get to it right away though.
Question: Automatic or 4+3 transmission?
Also, what issue are you having that makes you think you need an ECM?
I have an 86 vert and I can get you the numbers. I'm at work right now and can't get to it right away though.
Question: Automatic or 4+3 transmission?
Also, what issue are you having that makes you think you need an ECM?
Thread Starter
Instructor
Joined: Nov 2018
Posts: 113
Likes: 4
I had a performance chip installed and the car has not run right since, even took it out and went back to stock, Just pulled all the plugs and they are all fouled, the car is running really rich. Not sure what to do, I bought new plugs but not sure if they will get fouled also. It is an automatic trans.
Thanks for any help you can give me,
Jim
Thanks for any help you can give me,
Jim
Drifting
Joined: Jul 2022
Posts: 1,805
Likes: 365
From: Central Florida
Won't you need to put the new plugs in anyway ? My vote is put in new plugs and old ECM/chip and test it. Did car get rich at the exact time you put new chip in?
I don't think you would kill new plugs in a short test. What was the brand of chip ? Did you get the #'s they plugged in ?
I don't think you would kill new plugs in a short test. What was the brand of chip ? Did you get the #'s they plugged in ?
Thread Starter
Instructor
Joined: Nov 2018
Posts: 113
Likes: 4
Yes, I will need new plugs for sure. I will take your advise and try the new plugs first. The guy made me a chip for an 85, I told him it was an 86, so he made a new one. Yes it all started running bad after the chip install.
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Pro
Joined: Aug 2020
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From: Liliha Bakery stuffing my face with coco puffs!
AANM would seem to be correct for an '86 AUTO. ARAR is for a '89 AUTO which would have additional fuel added for cold starts as that year model the cold start injector is eliminated. Some people have gone that route to get rid of the CSI.
What's the reason for the new PROM? Did you ask for anything to be programmed differently? i.e. fan on/off, EGR disable etc.
Curious as to what was sent when the '85 PROM was sent as if not mistaken, '85 uses a 24 pin PROM and not the 28 pin. Also '85, you wouldn't need that G1 memcal adapter in the pics^^^you posted.
Thread Starter
Instructor
Joined: Nov 2018
Posts: 113
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I asked to have it made to get more horses, run cooler, smog delete, It may have been an 89 that he sent first. The fans were suppose to come on earlier to run cooler, they didn't come on all, overheated. I told the guy and he said he has been in the business of making the chips for years, he knew what he was doing. NOT! Maybe when I used the first one if it was for an 89 could have fouled the plugs and made it run rich. I'm just a backyard mechanic, I'm just guessing here. The next step may be to the Chevy dealership for repair. instead of throwing all kinds of money at it trying to guess what it is.
Thanks for trying to help me, it is appreciated.
Thanks for trying to help me, it is appreciated.
Pro
Joined: Feb 2009
Posts: 655
Likes: 164
From: Vancouver Washington
Smitty,
Are you back to the original prom and still running rich? If so then a check of your fuel pressure regulator is in order. The quickest way is to pull the vacuum hose from the pressure regulator and smell for gasoline. There shouldn't be and fuel odors in the vacuum hose.
If this all started with the new prom then returning to the original prom should correct the issue.
As previously noted 1227165 is the number on my 1986 ECM.
Are you back to the original prom and still running rich? If so then a check of your fuel pressure regulator is in order. The quickest way is to pull the vacuum hose from the pressure regulator and smell for gasoline. There shouldn't be and fuel odors in the vacuum hose.
If this all started with the new prom then returning to the original prom should correct the issue.
As previously noted 1227165 is the number on my 1986 ECM.
Thread Starter
Instructor
Joined: Nov 2018
Posts: 113
Likes: 4
Well today I installed a used ECM and the car did start, (ran like crap) Then some how it did start to idle and stay running. I thought it was fixed, until I shut it off and tried to restart it, it wouldn't star unless I held my foot to the floor, took my foot off the gas and it would stall. seems to run cold, not once it warms up/ Any Ideas for me. I hate to keep throwing money at this and not getting anywhere
Thanks for any help
Jim
Thanks for any help
Jim
Melting Slicks
Joined: Apr 2001
Posts: 2,115
Likes: 221
From: Ca.
Go back to the original ecm and prom. new plugs. Then you have to have a scan tool or software with live data to see what it's actually doing. Let us know what the blms' are after closed loop/warmed up.
Pro
Joined: Aug 2020
Posts: 647
Likes: 126
From: Liliha Bakery stuffing my face with coco puffs!
Well today I installed a used ECM and the car did start, (ran like crap) Then some how it did start to idle and stay running. I thought it was fixed, until I shut it off and tried to restart it, it wouldn't star unless I held my foot to the floor, took my foot off the gas and it would stall. seems to run cold, not once it warms up/ Any Ideas for me. I hate to keep throwing money at this and not getting anywhere
Thanks for any help
Jim
Thanks for any help
Jim