Hi Scotty, I have a 2003 Hyundai Sonata 2.4ltwith a PO100 code.also a PO350 .replaced MAF sensor spark plugs and lead also the coil packs, sprayed and clean the throttle body . but now revs fluctuate at idle ?????

If you still have those codes, they are notorious for bad wiring in those systems when that old. if codes are gone, try this video https://www.youtube.com/watch?v=NWCKvU2FmDc


so how would I go about checking the wiring ?????