Couple days ago, while my truck was parked at a park n ride, someone crawled underneath my truck and cut my catalytic converter out. Imagine my surprise when I fired it up! LOL Anyway, I'm thinking of just putting a straight pc of pipe in it's place. I'll be moving soon to a state where I don't have to smog the truck. But, since the 02 sensor won't be connected, I will constantly have the "check engine" light on. So, if something else goes wrong, the light won't tell me. Does anyone know of a way to "trick" the 02 sensor to avoid the check engine light? Truck would probably run better without a cat, huh?

 

99 v10 should only have upstream o2 sensor(s). ive run mine with a gutted cat for years now, and no light ever. there is no downstream sensor to tell it theres anything wrong. i am 100% legal here in MT.

 

This is the downstream side. Here's the wires for d.s 02 sensor. And when I drove the truck home the check engine light came on.
This truck was purchased new in CA, so that's probably the difference.

 

Run a straight pipe and a defouler should eliminate the check engine light.

 

That's exactly what I'd like to do.
Can you explain a bit more? What's a defouler?

 

There are O2 sensor simulators that you just plug in, look up MIL eliminator. A lot of the mustang guys run them with off road h pipes. A real quick search doesn't show anything specifically for a v10, but looking at rockauto the 1999 4.6, 5.4 and v10 O2 sensors all have the same part number so I'd assume anything for a mustang should work.

While you're under there you might want to consider doing the Y pipe mod.

 

It's basically an extension, pushing the sensor out. I don't know how it works, just that it does, as it worked on a car I installed a header with test pipe for.

If the truck has Ram horn style the y-pipe isn't worth it. I have it on my 99 and wish I didn't spend the money. The later trucks have a T and serious restriction which it does help.

 

[QUOTE=Bently_Coop;19295860]It's basically an extension, pushing the sensor out. I don't know how it works, just that it does, as it worked on a car I installed a header with test pipe for.

I was thinking that. I used those on my daughters truck. I think those are for when one has a bad cat, and they pull the sensor out of the air stream to "trick" it. I'm not sure it it will work with no cat at all. I'm sure gonna try it tho. A new cat is $400+

 

Just a spark plug anti-fouler. You can even double 'em up if needed. Mine had sort of a blind hole with a pin hole and I needed to thru-drill for an O2 sensor to fully seat.

Here's one chucked up, the collet is holding the male threads that'd go into your 02 bung.

 

Stick a cat on it...we all like clean air...

 

Amen brother!

 

if you gut or remove the CAT you are NOT legal anywhere, just because your state doesn't check. It is a Federal violation, very expensive if caught, although a very low probability of being caught. I also have no CAT.

 

These threads always turn into an "I'm a better person than you" debate. It's awesome

Me, I'm not worried 'cause COVID-19 is gonna kill us all. DUH

 

 

Some virtue signaling going on, fer shure.