Hello /pol/, my catalytic converter was removed and reinstalled to enable replacing another part.Since then I've gotten the CEL P2099 Post-Catalyst Fuel Trim System Too Rich (Bank 2). There's obviously a 99% chance that it's correlated.I'm a wrenchlet so I explained this to a mechanic, and they said to replace the post cat O2 sensor.Would that actually fix it, or is there a definitive way to know if it's something else, like an exhaust leak from the cat not being secured back on properly?Or maybe the O2 sensor was damaged in the process of reinstalling the cat and had to be replaced?I don't want to spend money on repairs targeting the wrong problem, because all that happened was removed and reinstalled the same part, so theoretically nothing should be broken... And I don't want to see the CEL after driving another 100 miles.
>>29024546>Hello /PolGas the bikes,race car now
>>29024554Oh this is r/o, I forgot
>he drives a gasoline powered car
>O2 sensor was damaged in the process of reinstalling the cateasy to damage especially if not taken off firstlots of vibrations from impact or cutting off old catprobably got tossed/fell onto the ground when removingthen removed/reinstalled with an impact>exhaust leakit would likely be noticebly louder to trip a cel. easy enough to check, just stick you hand over the flanges.>definitive way to knowhook up a code reader to see if readings are open or out of boundshonestly even a noob can diy it - drive up on a curb and be done in 15 minutes + $30 part instead of troubleshooting other shit
>>29024676>>O2 sensor was damaged in the process of reinstalling the catCame here to post this.
>>29024676>>O2 sensor was damaged in the process of reinstalling the cat>>29024682>Came here to post this.This and / or wiring harness or plug damaged or poorly connected.>>29024546OP, it's easiest just to replace the O2 sensor, and be sure to inspect the wiring harness + plug.Cite the make and model of this vehicle please, so we can help you with specifics and for code reset and such
>>29024546Yeah, coulda been damage. O2 sensors are generally bastard-tight, from heating/cooling cycles and corrosion. If the mechanic had to pull it, for working clearance, it may well have been damaged.
The post-cat O2 sensor is not used for air fuel calls. All it does is get compared to the precast to see that the cat is working.What you want is to extend the sensor away from the pipe with one or two O2 sensor defoulers, picrel.
>>29024546I would put money on you didn't line up and tighten the flanges enough and have a small exhaust leak but uts acting more like a vacuum and sucking fresh air in and throwing the sensor off. Or, you dropped the assembly hard enough of the sensor to fuck it up, forgot to plug it in, or fudged the wires somehow. But i just reread this and now understand you had this done. Doesn't change diagnosis, just that i cant say "go look at XYZ"
>>29024635Deleted diesel and Pre-emission master race reporting for duty
>>29024966>get compared to the precast to see that the cat is working.Thats the code thats being thrown
>>29024546it could be an exhaust leak. assume a small leak before upstream sensor.>upstream sensor gets fed outside oxygen and reads lean>computer responds by adding too much fuel>downstream sensor reads richif you have access to a scanner that can measure o2 sensor voltages, i would compare the upstream and downstream sensors.
>>29026655Diesel is gasoline like house music is techno.
>>29024546>my catalytic converter was removed and reinstalledYour working cat was replaced with a unit that is stripped-out for precious metals. This is happening a lot at shops in the Houston area.
