The o2's need to be unplugged to keep them from telling the PCM its running rich. Fresh air gets on the o2's and fools the compter into thinking its running lean, so it starts dumping lots of fuel. You'll foul out a set of plugs quick.

 

Okay, I understand the part about the fresh air hitting the o2's and making the computer think it's running lean and dumping the fuel in to compensate. But wouldn't unplugging them make this even worse? What will happen when I unplug the o2's?

 

The o2's don't register anything, the PCM thinks they are showing a neutral .500 so they make no adjustments to the fuel trims. The PCM will consider them broke after so long, but it takes a while. Since the o2's are showing a dead nuts neutral, it makes no adjustments to the fuel trims.

 

I drove my truck 15miles on open headers to the nearest muffler shop. The truck wasn't smoking at first, but once i got to the city, it started smokin bad . I had a blast watching the expressions on people's faces when i'd rev the truck at a stop light It was loud as hell, and since i had my windows open, the cabin smelled of exhaust for about a day or so then it went away. I had my O2 sensors on at the time and the truck still smoked. I'd say go for it, I had the same question about mine until someone posted that they ran their truck for two weeks on open headers ...Let us know what happens

Good luck and enjoy the ride

SLA

 

That's funny. I wonder why it was smoking? Flyer, maybe you could clear this up?

 

WHAT UP FLYER!?!

OR...........you can just leave them alone and make up some short extensions until you get your exhaust on, worked for me.

 

How long would the pipe need to be and what would I need to fabricate the extensions?

 

not too long, mine were only about 6" or so. all you would need would be two collector flanges and some pipe welded on the back of them, then just bolt them up and off you go. oh yea, enjoy the sound and the looks you will get!!

 

I Have Drove My Truck For Weeks With Cutouts Open

 

Smoking after the trip is from the o2 getting fresh air across them. The exhaust pulses, on the pulses, fresh air is sucked back up into the collector and messes the readings up on the o2 sensors. It does this no matter how rich it's running, so the PCM ends up adding as much fuel as it can.

Extensions will work also, but they need to be closer to 12" or so.

Hey TT, been back to the track lately?