Gotcha... I thought about taking o2 sensors out and seeing how it runs cause its idleing at 1500 and when it kicks down to where it supposed to idle it almost stalls out then revs back up. I am ordering some cats today.

 

i have changed everything and it still runs like crap... no codes on computer light not on any suggestions?

 

So, you have replaced the cats that were glowing? Cleaned the MAF sensor, changed the fuel filter, ran techron in the fuel? Checked for vacuum leaks? I still think it is a vacuum leak. All signs, including your prematurely toasted cats point to a lean condition. Your P0171 and P0174 have not come back? Have you checked your fuel pressure?

 

Did you shake the mufflers when you had the cats off? Sometimes the cats break apart and can clog the muffler, this would give you the same symptoms as a bad cat.

What do you mean "runs like crap" that can cover alot of territory.

 

YES. I have done everything and still runs rough and sputters when i lightly hit the gas to take off or when i stomp it... There is no codes to read the light is not on and as far as the muffler goes I took it off and ran straight pipes cause there was particles in the muffler. It will go 100 if on interstand and let it take its time but u have to stomp it if you press accelerator gradually it spits and stumbles.

 

Got to be a low grade misfire. If your cop's and plugs are new... and since your fuel filter looked like mud, I would check fuel pressure. Injectors are probably dirty as well.

 

Just left the dealer and they said its the cop's... WTF..

 

Those are the original cop's from your previous engine? Then most likely.