02 grand am se1 22l cant track down power loss

[Rick1488]

I have been experiencing power loss when I stop, it seems to pull the rpm's down a little or drag on the engine and the head lights will flicker, It feels like the car is gonna die but after a couple seconds it's back to normal. I do have a service engine light on so I scanned it and came back something like emission above threshold or something close to that. I'll have to rerun it. I bought a New battery, New alternator and still no change. Please help I cant track the issue down.
Grand Am SE1 2.2L
117,103

 

[Kevlar]

When is the last time you had the A/C serviced and the compressor checked?

 

[melsg5]

You have to post the code from the scan.