I am looking to put aftermarket exhaust headers on my 2000 cherokee classic (4.0) with California emissions (4 o2 sensors) , and all the headers I see do not have places for the o2 sensors. Does anyone know how to "fool" the computer into thinking that the o2 sensors (all four) are working properly so the engine light does not turn on?

 

I think it'd be pretty hard since the sensors work by different O2 levels creating different resistance levels which are then run to the computer where it is evaluated along with the rest of the sensors. You would have to somehow simulate the appropriate resistances for all 4 of the O2 sensors. Just drill out holes in the aftermarket header for the sensors.

 

the o2 is in the pipe after the header

 

Have bungs welded in.

 

This should be all you need.

http://www.summitracing.com/parts/AAF-ALL34153/

 

EDIT- most exaust shops should have those and be the same or cheaper (no shipping)^^

this is the easyest way, bungs are cheap,10$ ish +labor, and any exaust shop could do this easly and cheaply. just order one you want and then have them add some in the same location as you have them in now.

or find a cali one. but i dont think that would be easy to find...

 

Yeah, one before and one after on each side. It's a two piece manifold.