any ideas why my 2004 f150 4.6 with a cai,flowmaster 44s and edge is revving up and down when my ac is on? it goes from 350 to 700 rpms when its on. any info would be great thanks in advance

 

anyone have any ideas?

 

Thats you AC compressor kicking on and off.... thats normal to a degree. 350 sounds a little low so perhaps your AC compressor has excessive drag pulling the idle down, or he PCM isnt compensating/bumping the idle that is should when the compressor kicks on.

 

My '06 5.4L does this as well with my edge and flowmasters and S&B CAI...it will idle at 660 RPMs then drop once every 30 secs to 560 RPMs

 

Sounds like your a/c compressor is kicking on and off because it is low on R134. This happened to mine.

 

It must be because I thought I've been feeling a lil warm air during acceleration