P0113, P0420, P0430 codes...

my 96 gmc 5.7 v8 vortec just failed emissions. luckily these arent the same codes as last year. lol
anyhow my strategy on these codes are as follows:
P0113- going to replace the IAT SENSOR and see where that takes me.
P0420/0430- going to replace old cats with a pair of MAGNAFLOW cats. Old cats have apx 230,000 miles on em.
I have headers and run true dual exhaust. hence the reason for a PAIR of cats.
What are the odds of these codes being corrected with the repairs i am going to make?
Any info would be greatly appreciated. Thanx!!

Sounds like you're on the right track.

With those miles, the cats are likely shot.

Before replacing the IAT, check wiring and connections and clean the IAT as will as the throttle body.

Wrong forum, by the way...should be in P0XXX.

Good luck and keep us posted.

Before you replace the cats make sure they are approved replacements by your I/M program.

well thanx for the info. i am VERY new to this site and hv no idea about the "wrong forum area" lol
as for the codes, i replaced the IAT sensor and that did the fix for 0113 code. it also knocked out the 0420 code. however the 0430 stayed, so i said to heck with it and used my 250.00 scanner/reader and cleared the sucker. hahaha the code hasnt come bk yet but now my CATALYIST on my scanner is blinking. tried to perform some drive cycles but to do the "correct" drive cycle u need NO traffic or stops. kinda hard to find that in my area especially at 0600 when ev1 is enroute to work. nevertheless, my truck DID pass emmissions this morning so i am good for another year. thanx again!! sorry about being in the wrong forum area