2006 Tribute V6 3.0L popping thru intake

[KBWood]

102,000 miles. 2 weeks back wife said car stalled and AC abruptly stopped. Codes read 352,354,355. Ordered motorcraft platinum plugs and delphi COPs and replaced all 6 with upper plenum gaskets. Car still running rough and making a popping sound through intake that can be heard louder if unclipping air filter slightly ajar. It's intermittent like "whoomp whoomp" then nothing then maybe 1 or 3 whoomp sounds every so often, etc. Will go buy a vacuum tester gauge and AC manifold gauges to begin more troubleshooting soon. Just wondering if anyone had input in the meantime. Also if I swap fog light working relay with AC one, still no luck... but if I jumper 2 of the slots under where relay plugs in with a wire, then clutch engages and cold air will blow. Thanks all.

[timd]

Popping in the intake would seem to indicate a timing problem (sparking when intake valve is open). Perhaps a stretched timing belt/chain?

[KBWood]

It was actually the Computer after multiple plug firing test light led stuff. CircuitBoardMedics to the rescue with a cpu swap hooked it up. Very rare I know, but not in these models apparently.