Hi folks , im new to this forum and this is my first post . Ive got an 03 F250 with a 5.4 . I was looking to get a little more rumble out of it so i put a cheap cat back dual exhaust on it and to my dismay its just as quiet . I thought it was the cheapo flowsound muffler so i took it off and ran it with just the cat . It was just as quiet , . my question is will it throw a CEL if i gut the converter or put a test pipe on it ?
There is only one cat and its a big one , good thing is there is no 02 sensor behind the cat , i thought this was weird but it was stock exhaust so i figure that must be the way it was . Anyway Has anyone tried this and if so how did it sound and did a CEL show up after ?
Thanks .

 

There might be an O2 on top of the cat itself. That's how it is with F150's on the 2 cat setup.

 

Long tube it!

 

What do you mean by "long tube it " ?
And does anyone know if the CEL will come on ?
I didnt have this problem with my last two F150s , they were easy to get some sound out of . a cat back system and they sounded nice . This thing seems to be all corked up , I couldnt believe how quiet it was running with the exhaust cut off at the converter . But given the size of the converter about the size of an 18 pack end to end it no wonder why . I just hope it doesnt sound like an old dump truck uncorked .

 

If there is no O2 sensor after the cat I wouldn't think it would throw a code since it is monitoring before the cat, it's when there are 2 sensors that it starts throwing codes I believe.

 

This weekend i went for it and removed the cat completely and replaced it with a cherry bomb glasspack and WOW ! , thats what im talking about mister . Now it sounds the way its supose to . Its not obnoxiosly loud outside and doesnt even sound loud in the cab Sound nothing inside like it does outside , thats what i was looking for . I tow a big camper and didnt want to be deafened while towing. Doesnt have that annoying drone my last 2 trucks had with the flowmasters . No CEL either !. I was a little nervouse when i fired it up with just the glasspack and no muffler and tails , sounded like a 6.0 chevy HD with the MBRP kit on a megaphone but the flowsound muffler and tailpipes mellowed it right out . I am very pleased .

 

add long tube headers

 

My understanding is that second O2 sensor is to check for a clogged cat only

 

First Oxygen sensor is to measure a/f ratio of whats coming out of the motor which not on these trucks, but on new cars ive seen them come with actual widebands so the computer can more accurately adjust the a/f.

Second oxygen sensor after the cat measures how the cat is performing. It looks at the first Oxygen sensor and compares that to the 2nd to ensure that the cat is doing its job for emissions.

Any cat after that is just basically to "ensure" lowest emissions possible but with no oxygen sensor after it, you can remove it.