Ok i have seen the threads on making ur own mil elim's and my brother who i bought the car from is dumb and cut the plugs off can this mod still be done it looks like u can find the same color wires on the harness and just put the resistors and caps on it and it will still work any imput from any one who has done this mod will b greatly appreciated

 

I've heard of people making them with great success but i don't think they cost that much to buy legit ones.

 

You have to have the rear sensors installed and functional for MIL eliminators to work--the resistor and capacitor form a filter circuit that attenuates and phase shifts the signal from the rear sensors so as to trick the PCM into believing the catalytic converters are there and working--you can read more about his here...

 

so when u buy mil elims u still have ur o2 senz on ur car.... Im confused i thought u un plugged ur 02 and pluged in a mil..... This being the case what do i do about bout my harness being cut there is no plug where the o2 goes.... Does it even hurt ur cars performance with the back o2 gone i still have my fronts any help thankz

 

your ECU will throw a code indicating a lean condition and will attempt to compensate by running richer than normal (over a long period of time, this is not good for your engine life). and when you say the back o2's are gone, do you mean the wires are cut, or the sensors are completely out and there are just two open holes back there? if they are just open holes, you just made yourself a pretty cheap set of cutouts, not sure what the performance will be like, but thats sorta kinda what you're doing.

 

On our cars the rear O2 sensors have nothing to do with engine operation...

All they do is monitor the "health" of the catalytic converters and trigger a DTC if the converter is bad or not present...

 

i got the car from my brother and he cut the wire and all didnt even leave the plugs lmao he is a DA. There is enough to splice onto with new plugs but he had straight pipe welded in with a h so there are no holes for the missing o2's can i get them tuned out would thay be better than trying to buy a harness and o2's and making elims whats the best route im sure i need a tune but ill have my n20 this weekend dont wanna advance the timing any but im sure they can tune wthout advancing the timing.

 

if you can get a tune that will disable the rear o2's, you'll be just fine.

to cliffyk, when i put in my LT's and O/R H, the codes i was throwing indicated slow upstream readouts indicating a lean condition, and the car was running a lot richer at idle, as you could smell it pretty strongly. after i put on my tune, that all went away.

 

Yes, upstream I.e. FRONT sensors. The "stream" being referred to is the stream of exhaust gases, it flows from front to rear making the front sensors upstream and the rear sensors downstream.

Long tube headers increase the physical distance from the exhaust ports to the front O2 sensors, this means it takes a longer time for changes the PCM makes in the mix to be "sensed" by the front sensors.

There is a table in the tune named the O2 Transport Delay that defines the amount of time, at certain load and rpm combinations, after which the PCM should see a change in commanded AFR, as reported by the front sensors.

The values in that table need to be increased when LTs are installed.

The rear sensors do nothing but monitor the catalytic converter efficacy...

 

ahh so thats what special forces changed to accomodate for the LTs.. i understood the difference/function between up- and downstream, but i always thought, for some odd reason, that the upstreams o2 sensors were being thrown off by the downstreams since i never threw a code concerning the downstream. thanks for the enlightenment