OK hear me out on this one- I'm not painting it to look pretty, but instead guard against salt corrosion. I do drive my car in the snow and at 205k miles it's far from a show car

You may have seen my thread a few months ago where I was throwing a code and found it was a salt damaged PCM. My theory is there must be some low level electricity going through the case which slowly causes the PCM to attract salt and corrode with galvanic corrosion, though there isn't a dissimilar metal in physical contact. Other cast aluminum parts like the differential, torque tube, transmission and engine didn't show nearly as bad corrosion.

Thus, I plan to use an aluminum primer, and then several layers of spray paint. I don't care what it looks like, but I don't want my PCM to turn into what you see below again. Granted, the original one lasted for 18 some years, the 97-98 PCMs are a rare commodity these days
I'll be more diligent in using Salt Away in the wheel houses after each season from now on too.

Not sure if the paint would affect the cooling, the unit is ribbed I presume for strength rather than heat sinking.

Thoughts? Experience?

 

No real suggestions for you, but that old PCM sure looks nasty.

 

The paint won't hurt anything, I've seen it done lots. In this case will surely help.

Have at it!

 

That looks like damage from a leaky battery

 

definitely does.

 

I think I would try to fab up something to box in the pcm and seal it and the connectors from the outside elements before painting anything

 

Nope, sure wasn't. I've had the car for 13 years, and always had AGM style batteries in there. No damage to the harness at all. Besides the connectors are at the bottom of the PCM, the battery would have leaked acid from the top.

Starting prep already

Yup, looking into that too. I'm just glad the connectors were readily available, though repinning is a pain . Definitely going to put a healthy dose of dielectric grease and check behind the access panel after each winter season.

 

you are going to ruin the value of your car... it's "patina"

 

Going back to my modified air cooled Beetle days, painting is okay. Just use a flat black paint which actually helped cooling on those Bug engines. Radiator paint would also be good.

 

Spoils the whole "Rat PCM" experience completely.