This little light of mine ...

[Mr.Ontop]

Is probably going to cost me a damn fortune.
My daughter's check engine light came on last night. So today, I took it over to borrow a code scanner and see what's going on...it was this. Generally, I think this means it will be an emissions issue....which is never easily diagnosed or repaired..I think it may end up being the catalytic converter, and that's not gonna be cheap. What say you, wrenches of the web?

[tophercrowder]

@Mr-Ontop A little square of black electrical tape will make that go away

[pos_camaro]

@Mr-Ontop Maybe an O2 sensor or bad cat. One is a lot cheaper than the other.

[Krusty Walnut]

@Mr-Ontop O2 sensor? You can buy some of this stuff to clean the cat.

https://www.autozone.com/fuel-and-engine-cleaners-additives/fuel-additive-and-cleaner/p/cataclean-fuel-cleaner-16-7oz/227800_0_0?cmpid=LIA:US:EN:AD:NL:1000000:PER:8362741362&gclid=EAIaIQobChMI7KXFiNPx9gIVwAytBh204wVvEAQYAiABEgLl8fD_BwE&gclsrc=aw.ds

[sony1492]

@Mr-Ontop Can't tell you what'll fix it but here's a useful article about how that fault gets detected.
https://www.google.com/amp/s/www.carparts.com/blog/p0421-code-warm-up-catalyst-efficiency-below-threshold-bank-1/amp/

[Highlander]

@Mr-Ontop https://thumbs.dreamstime.com/z/cat-sign-rum-prison-beige-his-neck-says-bad-holding-bottle-black-lineup-background-167814463.jpg

[Mercedes_Pagoda_230SL]

@Highlander said in This little light of mine ...:

@Mr-Ontop https://thumbs.dreamstime.com/z/cat-sign-rum-prison-beige-his-neck-says-bad-holding-bottle-black-lineup-background-167814463.jpg

@cotd

[Zymosan]

@Mr-Ontop

Here’s what you do. Cut the cat off like a meth head and sell it. The use the funds to fix it. Straight pipe on the exhaust.

Some one ganked the cat from our work truck, so we went straight pipe because, Oklahoma.

[pip bip]

@Mr-Ontop start with sensors

[A Former User]

@Mr-Ontop

So before throwing parts at it you can actually easily diagnose this with the scan tool. You go into live data and look at the data from B1 S1 and B1 S2. You want to look at the switching time of both. S1 should switch quickly as that's reading exhaust straight out of the cylinder. S2 is measured after the cat (without knowing the specific car I'm assuming it only has two sensors per bank). On a good working catalyst S2 will remain relatively stable. If it's not you've got a bad catalyst.

You can also get under the car with a heat gun and measure before and after the cat to give you an idea if it's working or not.

former smog inspector and repair technician here. I saved many customers much money from not just throwing parts at.

[Mr.Ontop]

@tophercrowder Unfortunately my state is ridiculous about that sort of thing.

[Mr.Ontop]

@His_Stigness Thanks! I'll see if that works