Need some help on a 86 ECM?
Thread Starter
Race Director
Joined: Jun 2005
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Need some help on a 86 ECM?
I have a 86 4+3 and I am parting out a 86 Auto, I want to keep the computer but my question is: can you simply swap one for the other or are they programmed different? I know the 4+3 has the upshift indicator and I was wondering what tells this light to come on? Thanks for the advice, when it comes to the computer I am totally lost because I do not know if it a ECM, EPROM or is it called anything else. Please excuse my ignorance.
Team Owner
Joined: Mar 2000
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From: Boston, MA
To answer your other question, yes they are programmed differently. The 4+3 cars had multiple programs depending on if they had the MK2 overdrive included with Z51, or the MH5 overdrive. Besides that there are overdrive specific commands that aren't used the same way in the Automatic programs.
Thread Starter
Race Director
Joined: Jun 2005
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Thanks scorp508 for the information, what started this is I noticed the fans come on at a lower temperature than the stock setting on my 86 4+3 so I think there is a hypertech chip or something else in the car right now, so in order to put it back to stock I need the PROMM reprogrammed to the stock setting, correct? I kind of thought it was not going to be as easy as plug & play.
Le Mans Master
Joined: Feb 2006
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From: Louisiana
The main fan settings are burnt into the chip and controled by the ECM. The aux fan (if you have one) is contoled by a switch in the right head. Just plug and play. You may notice differences in the way the car operates now with the parts car chip. Only way to change anything in the chip is to have the setting erased and new settings burnt into it.
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Thread Starter
Race Director
Joined: Jun 2005
Posts: 17,640
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
The main fan settings are burnt into the chip and controled by the ECM. The aux fan (if you have one) is contoled by a switch in the right head. Just plug and play. You may notice differences in the way the car operates now with the parts car chip. Only way to change anything in the chip is to have the setting erased and new settings burnt into it.
I do have the Aux fan and when I ground the sensor between cyl 2 & 4 the fan comes on so I know that works, I kind of thought I would have to have the stock files put back on the chip in order to get it back to stock, I know that could open a can of worms around here with what temps the fans should come on.
Le Mans Master
Joined: Feb 2006
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From: Louisiana
I do have the Aux fan and when I ground the sensor between cyl 2 & 4 the fan comes on so I know that works, I kind of thought I would have to have the stock files put back on the chip in order to get it back to stock, I know that could open a can of worms around here with what temps the fans should come on.
You will have no way to know if the chips are stock or not, until you put them on an eraser. Just try both and see which you like.
Thread Starter
Race Director
Joined: Jun 2005
Posts: 17,640
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana