Drove my truck to work yesterday ('95 GMC Sierra K1500 5.7L V8) and on the way home started to idle high and I'd here a sort of quick whoosh noise from the exhaust after I took my foot off the gas.

Got home and pulled the codes from the engine:
35 - IAC error
51 - PROM error/ incorrect MEM-CAL

While I replaced the IAC about a year ago, I've never touched the VCM or the PROM. I've heard you could pull them out and reseat them in hopes for a better connection, but haven't tried this.

Any thoughts or advice?

 

Reseat them and see what happens. Make sure you touch a metal ground first you don't want any static electricity to damage them.