Car Backfires

[blageo23]

When I was driving my car today When i Accelerated 3/4 to full, at about 6000 to 6500 a loud bang happens, it sounds like a backfire. I didnt notice it before I installed my GM MAF and MAFT V2.02. Also I took the cover off the MAFT and when its at high RPMs or on off playing with the trottle the red LED blinks. What could be wrong? I do not have the 2 wires hooked up I read about it and one is for tuning with RPMs and the other for like nawz. If someone knows what it could be let me know PLEASE!
Thanks,
Mike

[blageo23]

Anybody know what this could be?

[DSM1G]

I had my blow off valve being vented to the atmosphere and sometimes it would backfire when I let off of the gas. So then I reconnected the hose and it was fine..

Dont ask why

[CVD]

Do you have a logger or anything?
I used to think I had bad fuel cut/stuttering between 5500-6000. Car wouldnt rev above that. Then I got a datalogger and realized I was riding the rev limiter, I just had a REALLY slow tach.

[blageo23]

I do not have a logger. I really need to get one tho.