98 sonoma 02 sen.

how do i change the o2

i couldn't even get mine out, had to take it to a shop, and have it drilled OUT. I spent 3 days off and on, that bitch was welded on because of the heat.

The easiest way if it doesn't come right off is to hose the area down with a good penetrating lubricant like liquid wrench. Then using a 6-point 7/8's box wrench and another larger box wrench on the end of it for leverage turn it counter clockwise... If you don't have enough room for the length of an extra wrench, use a hammer and bang on the 7/8 box wrench a few times. When installing the new o2 sensor, use anti-sieze on the threads.

I've never had a problem removing them. I got a tip years ago to let the engine warm up a little before messing with them. I've never tried removing one cold, either letting it warm up works or I've just been lucky.