Oxygen sensor question (1 Viewer)

[prerunner84]

I had a engine code 21,24 replaced both upstream o2s. I’m still getting the codes. The o2 harness connectors from the truck are in pretty bad shape. I checked to see if I’m getting any signals from the truck side of the harnesses and I am. Any help? Thanks

 

[Road Apple]

I assume you’ve searched, but just incase you haven’t, these threads might help?

“So, I decide to get out the FSM (I know, about time) Went through the test and the O2 sensor was working fine, but the heater on the sensor was inop. All test indicate the ECM needs to be replaced.”

Code 21

My '93 has had the check engine light on since i bought it. checking the codes I found a code 21. The O2 sensors looked like they were original so I replaced them with aftermarket Bosch sensors..... Still had the code 21. Waited a few months and decided to go ahead and order Toyota O2's...

forum.ih8mud.com

94 FJ80 CEl codes 24 & 25

Hi yall, i have a few other post on here for others issues but just recently my CEL came on. First time in the 4 months i have owned it. I get Code 24 & 25. Not sure what would make these codes pop up. Also i have noticed that when ever i undo the gas cap to fill up pressured air releases for a...

forum.ih8mud.com