Do any of you guys have this problem. It just started hapening the other day for me. Basically I'm driving on the highway say about 80'ish. Then I just release the gas pedel and just let the car downshift and slow down I hear like a pop coming from the exhaust. Is there like backpressure or something?

Stock or aftermarket exhaust?

Is it backfiring? Perhaps a rich fuel/air mixture? Faulty plugs?

cool!

I'm running an evo exhaust catback, test-pipe,y-, sc'd as well.. Running on one-step cold plugs..

Any ideas?

Are you running a BOV?

That's a coincidence because it started happening right after I installed my Blitz BOV.. Could that be the case? But why?

It may be a problem but it may be normal. I have no idea why it should be popping at 80mph. Whenever I start up my car in a cold start and give it some brisk revvs, the exhaust pops as the revvs drop. Sounds cool. Domestic V8's do it with aftermarket exhausts ALL the time, but our engines are smaller. Maybe your exhaust pops at 80mph becuase the S/C is forcing alot more air through the car vs. N/A and that causes your muffler to have more popping.

sound from my backside when releasing gas...other times when I release gas it's more of a 'pffft' sound...wonder what that could be?

check the sphincter valve for proper operation.

I do have a test pipe on mines just like someone in the thread had...But I do have an AFC installed and it was dyno tuned... Maybe since I drove it around after the afc was installed the ecu somehow remapped itself?

According to Apexi's website, "On hot-wire vehicles, the Deceleration Air Flow Correction function is capable of curing the erratic idle and stall problems associated with open-atmosphere blow-off valves on hot-wire air-flow meter systems."

Did you tune the "Deceleration Air Flow Correction function" setting?

Nope I didn't do that part.. Any tips on doing this?

Sorry, I'm just passing along the information. I don't have a SC or S-AFC, so I'm not qualified.

However, Kev or others will know how, so ask that in the forum.