Ok a while back i had loss of power at around 4000rpm & up, and i though it was becuase it was a 230hp power 5.4t,but now i have to punch down on the pedal to go up a SMALL hill!, and dont forget im wasting a bunch of gas! but im not sure whats causing this! but i think its the Cats, im not sure but i do hear something popping under the truck after i turn it off, and if it is the cats,what should i do to fix this? please help me and thanks!

spec.
5.4
4wd
255000+miles

i was thinking straight piping it but what size pipe is it? and will this cuase any mechanical problem or check engine light?

 

sounds like cats. got to your local muffler shop, have em chopped out and have em put in some magnaflow 94106 high flows and pipe to make up the difference. you getting any codes?

and also...search is your friend...

 

I was talking to a guy that did my pipes and he told me that all 96 fords and up, you cant use universal cats because they have a check engine light issue is this true? or is there a way to avoid this?

 

He either doesn't know what he's talking about, or he's a liar trying to get you to buy some OEM's off of him. Magnaflow 94106's work fine, but you have to mount the O2 bungs in the pipe after the cats.

There may also be an underlying issue with the engine if it isn't the cats.

 

x3, he doesn't want to do the extra involved work for a smaller fee, basically, he wants the profit, instead of you, the deserving customer.

Any cat that has the proper GVWR and a OEM spec catalyst will operate just fine, with the rear O2s mounted after the new cats. The Magnaflow #94106 cats are 9" long ( short! ) and have a 6200lb gvwr rating and are built as good as OEMs. Just no sound resonating, and a much smaller case. Go this route, and have the rear O2s re-mounted 1" behind the new cats and you will not ever get a CEL thats exhaust related, guaranteed.

 

well he priced me for it was 390$ to do the job, and i really dont want a check engine light one because i hate them!!! thats why i got rid of my old suburban because of that **** kept coming back on!!!

 

94106's are $96 for the pair on performancepeddler.com with the coupon code " clubgp". That should save you some cash there.

 

thanks alot for your help guys but i still kinda confused, ok why do these truck have 2 cats? dose
that mean i have to buy both? im not sure which cat is gona bad. How can i tell? 1? 2?

because if the first one is the one thats gone bad why should i replace the second on? please help me

 

'97 - early model '05s all had four converters. They did this because Ford was striving to be the most EPA efficient to look good to the tree huggers.

You can remove the fronts and keep your rears only without any problems ( trusting that your exhaust man can fully weld around to prevent leaks ) and have no CEL, but the whole Y pipe will need to be dropped for pipe sizing issues. If it goes that far, might as well replace the 4 cats with 2 Magnaflow hi-flow units for better flow and sound gain.

 

Wow thanks you for your help! yes my uncle know how to weld so i guess im just straight pipe or just gut the inside out too the front cats and put new magnaflow cats in the back,

 

Ok i finslly got my new cats on for $150 and removed the 4 but my truck still feels sluggish!!! Can u guys have any idea whats wrong? i dont have check engine light or nothing like that but i cant figure out the PROBLEM!!!Im thinking its a stupid sensor some were or somthing else, any clues?

replaced MAP
airflow sensor

 

Have you done a full tune up? With 255k I would imagine its not going to be any speed demon. My neighbor's dad has a '00 Silverado 5.3L with 221k and I drove it to my house when I was detailing it for him, those are a quick truck all stock but an engine that aged it was weak.

 

well true but my brothers 4.6 has 202,000miles and yet its feels faster and can tow more then me and he dont even done a tune up scene they got it.But yes i did full tune up back when she had 212,000miles i put new:
Fuel filter
oil filter
transmission filter
all fluid change exept rear end
spark plugs
coil+wires

but i did notice that they have a hose that goes to the back of the engine and has like a little tube looking filter but i dont think that little filter would be causing that.

 

o..nvm she runs awsome with a/c off i was driving it before with a/c mac LoL

 

That could mean that there is a problem with the AC compressor if you're noticing substantial power loss with it on.