100% Free

No Scanner Needed

Carly logo
Prices

helmutstorm6

Lexus ES Exhaust Treatment Malfunction

I'm at my wit's end! My 2019 Lexus ES hybrid is giving me fits. The check engine light is on, it's running rough, and I swear I can smell exhaust fumes, maybe even a leak. It's got 185222 km on the clock. I thought maybe it was low on DEF fluid, but that's not it. What could be causing this awful exhaust treatment malfunction?

Summary of the thread

A 2019 Lexus ES hybrid is experiencing an exhaust treatment malfunction, indicated by a check engine light, rough running, and exhaust fumes. Initially suspected to be low DEF fluid, the issue was later identified as a faulty lambda (oxygen) sensor. Replacing the sensor resolved the problem, eliminating the exhaust leak and smell.

Did this summary help you solve your problem?

4 comment(s)

williamkaiser5

Sounds familiar. I had similar symptoms with my old BMW after its oxygen sensor went bad. Rough running, engine light… the whole shebang. Ever had the oxygen sensor checked?

helmutstorm6 (community.author)

An oxygen sensor? Could that really cause all these problems? I thought that just affected fuel efficiency, not the exhaust system itself. How did you figure out it was the oxygen sensor on your BMW?

williamkaiser5

Well, the O2 sensor tells the engine how to burn fuel efficiently, and a bad one can mess up the whole combustion process. Think of it like a chef with a broken thermometer. He might try, but the cake will burn. I didn’t figure it out myself; my mechanic ran a diagnostic. I'd suggest doing the same.

helmutstorm6 (community.author)

It was the lambda sensor, just like your oxygen sensor! The garage confirmed that the exhaust leak and smell were also consequences of the bad sensor. Repair cost me 375€. I appreciate the help!

rmh_community_comment_box_header

community_crosslink_scanner_headline

community_crosslink_scanner_intro

community_crosslink_scanner_title

community_crosslink_scanner_price

community_crosslink_rmh_headline

community_crosslink_rmh_intro

community_crosslink_rmh_title

community_crosslink_rmh_subtitle

community_crosslink_rmh_brand

LEXUS

community_crosslink_rmh_model

ES