it would be really nice not to have to worry about the o2 sensor so then i could do anything i wanted with the exhaust. ive read a few threads about the fastman o2 simm. do they still make it? and since i have a 1998 what do i do with the down stream sensor?

 

The fastman sim would plug into the downstream sensor plug. You can then throw away the old sensor.

The upstream sensor (pre-cat) needs to stay where its at. It helps your PCM determine the air/fuel ratio. Without it, you will get all sorts of weird things happening, the least of which could be loss of power and gas mileage.

 

so is there anyway of fooling the pre-cat sensor? other than the non-fouler trick?

 

The pre-cat sensor has nothing to do with your catalytic converter. What are you trying to "fool it" out of? It is 100% necessary for your truck to run properly.

The post-cat sensor is the only sensor that has anything do with the converter. As a matter of fact, thats its only purpose.

 

id like to not have any sensors in the exhaust. is there anyway to do that and still have the have the ecm read everything right?

 

Nope, unfortunately not. The first sensor is essential to your truck running properly.

You'd have to completely convert your engine to be not controlled by a computer, or drop a new computer-less (old school) engine in (and therefore a new tranny as well). Neither would be easy, the first might not even be possible.

An O2 sensor should be good for at least 50,000 miles, if not more, unless you haven't fixed your leaking plenum gasket yet. I'd leave them be.