Ramodeys

I have an E55 with no cats and need help passing smog. I put spacers on the rear sensors so I am getting no codes for the downstream but am having issues with the upstream(pre cat). The issue I am facing is with the heated oxygen sensor. I am getting codes P0135, P0150, P0134. I read about using resistors to give a fake signal but online this is only done for the downstream sensors. I tried using resistors, 10watt 20ohms, but it did not work. On bank 1, I have p0134 which means no activity so I might have fried it. I am not sure why I am getting issues with the upstream sensors since with the removal of cats, usually the downstream sensors are the ones that face problems. Before the resistors, I got codes P0135 and p0150 which means circuit malfunction. I have midlength headers, I am not sure if this would have an effect on the upstream o2 sensors.

hachiroku

if you are having errors for your primary sensors that means your primary sensors may be faulty. the rears have nothing to do with the fronts, but if your fronts are bad, your rears can soon fail there after.

spacers should only be used in the rear's if bypassing check engine is your desire. much easier to have this coded out with a tune, but won't pass smog in california(not sure where you're from) if so. you'll need catalytic converters if you don't have them if you plan to pass legally.

Ramodeys

Thanks, I'll get new sensors for the fronts then. It strange they both failed at the same time after putting in headers. I am in Cali but the spacers cleared up all issues with the rears.

Ls1toAMG

I thought California had visual inspections. If they do, you will need cats.

Ramodeys

I am not worried about visual inspections, I know a few places that look the other way. I just have to get the codes cleared so it can pass.

bobgodd

Are any of these places in Southern California? I've had my headers for 10 years, and nobody seemed to care, but now I've been turned away by two shops for headers with no C.A.R.B. sticker.