2005 4.6L F150 --

At start up, start to hear popping noise and then after drive truck and turn off, hear popping noise again.

Usually about 5 to 7 pops each time and really can't hear going down road.

I think it's converters?

I have a an Edge Evolution CS Gas hooked up....set at Level 3. Normal air intake, and Flowmaster exhaust dumped in front of axle. Nothing fancy.

Thoughts? Someone local told me heat shields?

 

Popping coming from ??? Tail pipe ?? any codes ??

 

Is it in the cab? I know my HVAC makes a faint popping/groaning sound when I start the struck up and its already set to be on, and vice versa when I shut it down or turn the truck off. Maybe I'm completely off-base here but thats the first thing that popped into my head, because it sounded like something in the engine bay the first few times I heard it.

 

No codes. Sounds like in engine bay and not faint sound. Popping sounds like metal getting hot. Wonder if I could record and post link to video?

 

Any new ideas?