01 ford Taurus 24 dohc codes

i have three codes coming up and cant figure out how to keep them off. po442, po136, and po141. i have put a new fuel cap on it, and put 3 new o2 sensors. same o2 sensor, im just getting lost when it comes to fixing it and i know cars for the most part.

Well, you can keep throwing parts at it, or you can give in and pay the $100 to $200 diagnosis fee to find out what really needs to be replaced. There are troubleshooting flow charts for each code, and they don’t start with replace part X.

BTW, those should be “0” not “o.”

Dont know that this will help with all your codes but maybe for the P0141. Check fuse #28. If its blown you probably have a wiring problem for O2 heater.

Put the P0442 in one bucket, and then the other two in a different bucket.

The small evap leaks can be really hard to find if the gas cap doesn’t do it. (Did you closely inspect the filler neck for nicks or damage? You could coat the gasket with some petroleum jelly or something and see if that does anything). You may end up needing a smoke test but you can pretty easily inspect and/or replace all of the evap lines under the hood. Just find the charcoal canister and start following the lines. One part will lead toward the intake and the other back to the firewall. The small ones can’t always be seen. You could check them with a hand held vacuum pump or just replace them - vac line is cheap.

As for the O2 sensor - are you saying that you put 3 different on at the same location - downstream sensor on bank 1? Has it occurred to you to check the wiring and wiring harness for that sensor? Those codes don’t mean the sensor is bad. Though they would be triggered by a bad sensor they will also be triggered by bad wiring for the sensor.