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ECM Questions

08-18-2012, 09:20 AM
Where is the ECM located on a 1987 LeSabre Limited?
Also, if a replacement unit is installed, does it require any adjustments or is it correctly programmed "out of the box"?

08-18-2012, 09:52 AM
It's under the right side of the dash, you will need to transfer the the prom from the old ecm to the new one. There is a panel on the ecm that needs to be removed and the prom sits under that.

08-19-2012, 10:06 AM
Found it. However, there are NO readable numbers on the unit except for a paper tag on the side that does not seem to be any help. I can see where there used to be numbers on the front but they are too faded/worn to read even with a magnyfing lense. Any other way to figure out the correct unit to purchase? VIN any help?

08-19-2012, 05:21 PM
Check RockAuto (http://www.rockauto.com/catalog/raframecatalog.php)then select Buick/LeSabre/1987/engine, then click on electrical. Select "Engine Control Module (ECM)". It appears there were two different OEM ECM part numbers. Getting the correct one depends on finding the axle ratio listed on the SPID (RPO) code.

Blue Bowtie
08-19-2012, 05:37 PM
As usual, Hot-Z is correct. The 1K PROM for this series ECM is soldered down instead of the unit using the CALPAK carrier as other ECMs did. Once fused, the program is not erasable, so you really need to get one specifically for your vehicle, with all its options and specifications.

08-19-2012, 05:44 PM
OK, I am lost. Where do I find the SPID (RPO)???

08-19-2012, 07:34 PM
In the trunk under the deck lid, under the spare tire cover, and glove box are the 3 most common areas.

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