CATS n O2 Sensors

[DH22G]

Ok I was just at the dealer and i asked them if there was any possible way that they could go into the computer and turn off the o2 sensors so I could run straight headers while I finish some work on some things. Those who know my truck already know it is LOUD.. and I have already heard it with striaght pipes and without cats. But they were saying there is a way to bypass the 02 sensors with pulling some fuses n such. I was wondering if anyone knows what fuses do i pull?? so i can not worry about my 02 sensors throwin a bad code to the computer and screwin everything up?

[DH22G]

Ok I was just at the dealer and i asked them if there was any possible way that they could go into the computer and turn off the o2 sensors so I could run straight headers while I finish some work on some things. Those who know my truck already know it is LOUD.. and I have already heard it with striaght pipes and without cats. But they were saying there is a way to bypass the 02 sensors with pulling some fuses n such. I was wondering if anyone knows what fuses do i pull?? so i can not worry about my 02 sensors throwin a bad code to the computer and screwin everything up?

[Hummertech]

There is no simple fuse to pull to disable the o2 sensors. I guess you could just unplug them and run your headers with no sensors, your engine will definately not be very efficient and may even run a little crappy since it can't monitor if the amount of fuel it's putting in is too much or too little. Of course you will have a constant check engine light on also.
How about paying a few extra bucks and getting headers that have holes for the o2 sensors. Or taking your headers, and have a machine shop make you some threaded holes for your o2 sensors. Then all of the enviornmental wackos will love you for your concern for the envioronment. NOT.

[KenP]

DH, you can just get a bung welded on at any muffler shop.

[DH22G]

no guys... what i mean.. is while i am doing work on the rest of my exhaust I just want to run the headers. my exhaust already has spots for the sensors. that is no problem. iam just looking to what fuse to pull so i can avoid that check engine light when i fire it up without the sensors in place. and avoid it running like ****..


"But it just sounds so cool with straight headers!"

[Patriot]

I have heard of plugs you can get to disconnect the sensors and install these plugs thus giving a positive signal back to the computer...don't know if they exist for the H2 though....

[HUMMERcustoms.com/TAZ]

You could go to tuning software that has 2 bar density and some coming out with 3 bar soon.
Well anyway My point is with software you can just about make the engine do what ever you want. True it is a little harder but if You call around you may find a shop that has software for your year as the high dollar stuff is not vin specific it is vehicle specific. You can have them tune so that MAF is fooled all the time till you change it back and you should be able to do the same with sensors and basicly you are just fooling the PCM into thinking the stuff is there and working and it is not. I would think a tuning shop could help and not charge much. The sensor is reading the oxygen left in the exhaust which of course is telling the fuel inj. if it needs to lean or richen up everything. I would ask a tuning shop for help so you do not have to spend money on buying software but, if they charge like 350 to 450 then you need to buy the software and learn to use it. You can get a real good setup not with everything but for $500 to $700 then you do what you want when you want. They are not hard to learn to use.
TAZ

[madcat]

Taz, do you use EFILive ?

[DH22G]

thanks guys for the response. i think iam going to go back to my dealer first and sneak in the back. maybe con the tech a little.. but then after that. it is the performance shop.

if anyone has any other ideas please let me know!

[HUMMERcustoms.com/TAZ]

My tuning sponsor is HP Tuners and I use the VCM Suite 1.70 with I/O enhancment and 2 bar density and may be going to 3 bar density.
I really like it allot. Easily self taught. I'm going to set it up to run on My PC that We are building for the permenant install in H2 with 12 " touchscreen. Every time H2 starts the PC boots and tuning program loads so that it comes up in scan mode and I can run 100 mies and load it to edit and tweak and flash PCM. Run it more in scan and just conintually tweek it. I will be able to pull it up on the screen and see it running with another driver of course and watch it learning as We drive. Right now I'm waiting on some upgrades from HP as I'm running as much as -9 on air/fuel and it should be -1 or -2 which is just below being lean. I'm running fast and pouring fuel as the MAF is fooled and does not know what to do except dump fuel. My MPG will go up with the HP and torque when We get all the new equip. in from the sponsor. I will completely remove MAF from system.
TAZ