2000 Dakota SLT, 3.9 magnum. Basically I want my truck to be louder. My thought was of taking the o2 sensor off-therefore there would be a hole in the cat. I was wondering if this is bad for anything?


Along with this now that i think of it, my truck seems to run a little rough, and the engine light is on, is it possible that it is the o2 sensor?


Thanks- Chad

 

you want to remove the o2 sensor and leave it out? dont.... just get a new exhaust if you want it louder.

 

Is it bad for the truck? Im looking into a 40 series flowmaster, but their 80 bucks, and i am currently broke.

 

well if its the rear o2 sensor its only for emissions but its just like having a hole in your exhaust. just cut off your exhaust before the muffler. cheap and loud.

 

I'm kinda new at this, but i thought there was only 1 o2 sensor ( on the cat) at least thats all i seen? And i just wanna take it off and see if it sounds nice (even though i can never get the v8 sound) I would like to keep it with the o2 sensor off until i get a Flowmaster if it doesn't hurt

 

its not going to sound good, not all of the exhaust is going to go through that little hole, its going to sound like u have an exhaust leak.

well the there are lik 3 pre cats at least on the 4.7's. but thoes are for a/f ratios and should not be messed with.

 

@Chadp13

to answer your question YES it will hurt your engine.

think of it this way
O2 sensor #1, cat, O2 sensor #2

the computer compares the readings of #1 and #2 and adjust the fuel mixture.

If there is no reading from #2, or readings way out of sync with other, the fuel mixture will be way off.

this is the same reason you can't get rid of the cat either.

hope this helps

KillerKilgore

 

not true, the rear cat is stricly for emissions, as long as the rear or last o2 sensor has a differnet reading from the others its fine. you can remove the cat w/o problems. its just removing the o2 sensor isnt going to make the exhaust louder.

the pre cats are the ones that adjust a/f

 

Agree that removing the O2 sensor is just going to make it sound like it has an exhaust leak.

BUT think about it, if there is an O2 behind the cat it is telling the computer adjust the fuel mix and if it is still to rich that is why it won't pass emissions.

if the cat is gone the reading are going to be the same and computer is going try to lean out the mix again and again.

if the last O2 sensor gives a reading of too lean the computer is going to try to make the mix rich.

I won't swear to this reasoning but this is the way I understand it.
That's my story and I'm stickin' to it.

I really don't have to worry about emissions here in KY but you do in WVa which is 1/2 mile away.
KillerKilgore

 

do the 3.9's have an o2 sensorAFTER the cat? my 4.7 only one before. i thought the rears after cat only moniter if the cats working. but it dosent matter to me b.c i dont have inspection anyways