how do i know which ecu do i have

[streetknight]

i have a 1987 325 m20b27 engine. how do i know which ecu i have and where is it located? reason i ask is because i want to megasquirt it and the earlier motronic ecu has 2 sensors on the fly and the later 1.3 has only 1. which ecu is it?

[rs4pro3]

2 sensors on the flywheel, more then likely your ecu ends in the part number 021

[streetknight]

where is it located?

[Jordan]

above the glovebox, below the dashboard.

passenger side of car

[James Crivellone]

2 sensors on the flywheel, more then likely your ecu ends in the part number 021

86 and 87 had 027 ECU's, which allowed you to remove and install a chip (IE not soldered on)

[rs4pro3]

ya 027 removable chip
007 can't remeber if you can remove the chip in them or not
then 021 has the soldered in chip