Are the ECU's the same for a '74 and '75, are they interchangable?
Mine is a '74 2.0 but I also have a '75 ecu, are they the same?

See http://members.rennlist.com/pbanders/djetparts.htm and compare the numbers.

'75/'76 cars run quite a bit leaner. That may be an issue.

The Cap'n

Thanks...

I have a similar question on my '74 2.0.

The P/N on my ECU match those in the table from link. However, there is a three digit number (090) after the part number. Does anybody know what the 090 represents ?

Click to view attachment

Not to hijack this thread but have a question that might be relevant for others wondering about ECU issues. How can you determine what the ECU number is if there is no longer a sticker?

My testing of a 74 044 ECU and a 75 052 showed that the 052 ECU runs the AFR a half a point leaner, 13.7 to one vs the 052 14.2 to one. You can use the 052 but you should adjust the MPS to the correct 13.7 to 1 AFR. The 052 has the fuel shutoff when you are coasting til 1800 rpms so you do get better MPG.