I recently had cause to open the 165 ECM fitted to my 88 LB9 IROC and noted that the MOV surge suppressor had blown. I live in Australia where some parts are hard to find...I was able to buy and fit a recycled 165 ECM but would also like to repair the damaged unit.
Please will someone advise me where online I would be able to source spare components for these older ECM's. I know they can be returned to GM through dealers for replacement but doing that from Australia will be expensive.

 

Best bet may be to find another non-functional ECM and use the part from that one. I did check an ECM I have here and the MOV is marked as such:

TNR
4417
8551

The 8551 may be a data code (51st week and 1985, fits the ECM). The 44 may be the voltage rating. Just semi-educated guesses. And, a 44 volt rating shouldn't be too far off. This device is across the B+ line entering the ECM. So it needs to supress what is left of the starter kickback (typically 65 volts or so). Could go on the safe(r) side and try a 25 volt device.

RBob.

 

https://www.thirdgen.org/techbb2/sho...&highlight=MOV

Perhaps Vader would be kind enough to enlighten us as to the specifications he uses in replacements?

On an aftermarket OE-style replacement 1227165 I have here made by Delphi, MOV is labelled as:

GEP9
4417

Does seem to confirm 8551 as a date code. Can't find any info on 'em though.

 

I wish we had heaps of US junk yards here in Oz, mostly we have yards full of Holdens which did use a modified 165 (same as but 160 baud only)... or so I've read and I will try to find some of these.
The GM rebuilt ECM I'm now using "labelled 86 TPI V8" had a MOV marked "TNR/5037/8544". My original ECM exploded and was unreadable. I also noticed what appears to be the odd zener here and there on my original 88, but absent on the 86 version.