Diagnosing Catalytic Converters

On this episode of Fear No Fix, Chris and Jordan explain how to determine if your Catalytic Converter is working or not.
If you need to read codes or live data to help diagnose your issue, BlueDriver can help! Get the #1 Scan Tool on Amazon here:
Amazon.com:
www.amazon.com/gp/product/B00...
Amazon.ca:
www.amazon.ca/gp/product/B006...
Top DTCs (Diagnostic Trouble Codes) associated with Catalytic Converters:
• P0420
• P0430
• P0421
• P0431
• P0422
Top symptoms associated with Catalytic Converters:
• Check engine light
• Misfire
• Dark exhaust smoke
• Smell of Sulfur or rotten eggs from the exhaust
• Excessive heat under the vehicle
• Rattling sounds underneath the vehicle
• Poor fuel efficiency
• Poor acceleration
• Difficult to start
• Fail vehicle emissions test
Video Sections:
Intro: (0:00)
Reading Codes (0:30)
Physical Tests (2:28)
Outro (3:59)

[@shoa4566]

Big up to Scotty Kilmer for selling me on this blue driver. Saved my buns and I helped a few neighbors out too.

[@northsideangler8846]

My blue driver is a life saver wow keep the features coming keep updating it Scotty was right glad I listened to him.

[@lloydhlavac6807]

I recently bought the blue driver, also on Scotty Kilmer's advice. I'm also glad I listened to him!

[@losog2319]

man what dis make 3 of us they def need to sponsor scott fasho

[@elmo1220]

That’s 4 of us! I watched his video and decided to buy this after I couldn’t figure out which sensor when bad. This machine caught the problem. Hopefully I’ll be able to get my car to pass smog inspection

[@markurban273]

Guys - BEST VIDEO ON WEB for a cat diagnosis!!! Thank you! I have spent hours listening to other videos and now everything clicked with this. Brief yet thorough descriptions.

[@lloydhlavac6807]

I just did these tests today, both the blue driver O2 sensors readings, and the temperature gun test. The downstream O2 sensor was all over the place, and the temp in front of the cat was much higher then the temp in back of the cat, so looks like time to get a new catalytic converter.

[@jeffboe357]

Excellent work! Just got the blue driver in the mail. This will be the 1st diagnosis with BlueDriver. Great great great information. Thank you for putting this out. Just another reason to buy BlueDriver

[@LemurMonitors]

Good luck with the repairs!

[@mohammedkabli8225]

Nice info, Keep em coming!

[@geraldryan8562]

Thanks guys, keep them coming, especially SLK info, Merry Xmas 🧑‍🎄

[@JessySons]

Great info!. Thanks, guys!

[@dkruz1]

about 4 minutes into this video BlueDriver presenters said they would do a video on O2 sensors but I could not find that one.

[@keithp115]

I got a Blue Driver for Christmas and can't wait to use it!

[@LemurMonitors]

Any questions/issues/etc you can find our contact info on the 'more' tab in the app!

[@leolizcabrera]

Really good video, very instructive

[@paulpaquette1961]

You might want to make sure there are zero exhaust leaks first. Oxygen storage capacity can be determined by three consecutives revs and observing the post cat O2's behavior.

[@rodneyspence7441]

Will the temperature difference (between catalytic converter inlet and outlet) test tell you that the converter is bad/clogged apart from whether the downstream O2 sensor is working or not? In other words does a bad temp test definitely indicate a bad/clogged cat converter?

[@rudylima7013]

You guys are great

[@robert3325]

Great. Thanks for sharing

[@LIOTBs]

Thank you much I really appreciate that!

[@LemurMonitors]

Happy we could help!

[@WayneVLOGS]

Thank you. This video needs to pop up when you search p0430 or p0420. Note to find out why my cats went bad

[@dennyblazer1167]

Thanks guys and blue driver

[@williegillie5712]

I was thankful blue driver scanned all modules and found the issues with this 2006 Chevrolet Traverse 3.6 liter engine. The codes where probably due to the miss fire causing the converter to not function properly. All codes were erased and the scan done again, which found no problems after the fix

[@freddiejonesy6168]

Great video!

[@bobreichel]

My 2016 Ford f150 3.5 turbo catalytic converters temperature test is good hotter going out then in by around 100 degrees but still throws a code p0430. Checked the 02 sensors with my scanner and 02B1S2 (V) 790-815 / 02B2S2 (V) 290-805 // 02S11 (MA) -.063 TO .016 / 02S21 (MA) -.074-.004. Could it be the sensors and not the catalytic converters or something else?

[@ahtoh1]

good info

[@nymphowolf]

I need help please, im getting a P0171 code and a P0430 code on my 2007 Cadillac Escalade ESV with a 160,xxx miles on her, so far i replaced both right and left manifolds last weekend, i replaced bank 2 downstream 02 sensor, and now I just replaced the maf sensor thinking that was it, then i cleared the codes but they are keep coming back and even inspected for vacuum leaks and don't see nothing out of the ordinary. This is been stressing me out so bad. So far i spent a lot of money and nothing is seeming to fix it.. what should do, drive her to the junk yard??? I'm so frustrated over this and been trying everything!

[@juanjohntramos7196]

I have 2006 gmc 1500 savanna , 5.3L V8 . I just had the po332 knock sensor and harness replaced. I cleared the code . Drove the van for few miles , then the engine light came on . I checked and the code reads , po332 low input , pending . Question; 1. What does this mean ? 2. Is ok to drive 50 miles everyday for few days ?

[@Mias-trailerparkgarden]

I did emission 3 weeks ago and it passed . I got a 420 code bank 1 could it just be sensor ?

[@garciahome6036]

So far I see three (3) videos on this channel (KZbin). How often do you post new videos? Do you have another platform where you post videos?

[@billybobbarker3175]

I use the BD daily. Current project is a 2000 GM 5.3 LM7. Am getting 420. I have borescoped the inlet and outlet of the cat. The substrate looks ok at both ends. The upstream sensor is active but not uniform in oscillations. The downstream sensor is following the upstream almost exactly. I have fixed all exhaust leaks with new bolts and gaskets. I am down to replacing the O2 sensors. The only possible thing left would be a poisoned convertor. If gets to that I will try the lacquer thinner burnout trip trick. For now I have put in an O2 sensor spacer and 420 is totally gone.

[@salvadorguntherr9673]

Wow these are pretty nice video. I'm screwed tho. Its my catalytic cuz I replaced both o2 sensors and still got this code. 😒

[@gagemotorsports1074]

Thank you

[@sajjadmohammad3094]

Can we clean it with fuel additive

[@et2525]

Diagnosing Catalytic Converters

[@TOLDUSO4EVS7676]

Great thankyou

[@RatanaTan]

I have 3 sensors, it’s an 07 vw rabbit 2.5 B1 s1 located before the cat reporting in lambda B1s2 located on the cat reporting in voltage B1s3 located after the cat reporting in voltage I’m not sure how to read this

[@sprezie]

i was getting a 420 code, using live stream all sensors looked good with an occasional spike on bank 1 sensor 2. temps on bank 1 looked good, ~400 in and ~500 out so i replaced all the sensors with walkers upstream and bosch downstream. now i am getting spiked readings on both downstream sensors and the 420 code is back. any additional troubleshooting steps to isolate the converter?

[@LemurMonitors]

If you have a BlueDriver you can send us a email from inside the app (More tab, contact us, email) include this info and we would be glad to help you out!

[@williegillie5712]

You might wanna do an injector test. A bad injector can cause the catalyst to malfunction. Also a defective coil or bad spark plug can cause a rich condition in the catalyst. Lastly bad spark plug/s can cause problems also. Blue driver should scan and tell you if your O2 sensors are reading rich or lean. I’m thinking they will be trying to lean the fuel mixture to compensate for rich mixture in the engine

[@warrio3176]

What your email so I can sent you my data, maybe we can do a video for our blue driver friends.2007 toyota camry 2.4 (Po420) i want to learn how to read all this data. Thanks

[@RobertoSantiagoRodriguez]

Ok, my display looks different. Are you using iPhone or Android. I went in the settings and didn't see an option to get readings in that format. Tx for the video!

[@LemurMonitors]

In this video, we are using an iphone. If you are having any trouble displaying the data, you can reach our support team by going to the app, selecting More, Contact Us and then Email.

[@mike-yp1uk]

How do fuel trims effect your temp readings?

[@paulpaquette1961]

Rich Conditions will heat your up.

[@todaysupdate6824]

Hi, my check engine light on today . It say catalytic converter defect . But I have change it one month ago . Anyway I erase the code and check engine light gone . So my question is will it come back again. If so how long it will take to come back. Thanks Golf 5 ( 2008 ) 1.4 patrol engine

[@LemurMonitors]

If there's still a problem the code will be back eventually, how long depends on the severity of the issue and the car. Some minor emissions issues may take days to weeks to come back, while more serious electrical issues can sometimes come back so fast you don't even see the light flicker

[@SirCavemaninthewest]

Currently dealing with a manifold leak that's popping and banging at idle. I'm sure the catalytic converter needs attention too.

[@iam1smiley1]

Fix leak that lets unmetered air into the engine first before judging Cats 🐈

[@thebridge6967]

What if the downstream side is higher than 10% hotter?

[@Nathan-gi9mm]

My Bank 1 Sensor 2 is hovering at 0.065V while sensor 1 is up and down like the video shows. Does that mean sensor 2 is shot?

[@LemurMonitors]

Hey Nathan! We got your support email and will be reaching out there soon!

[@jeffb3632]

No, it should be constant around .650. Means the catalytic converter is working.

[@dragonstripes]

I have had both the catalytic converter and O2 sensor replaced and I'm still getting this code. Where do I go from here?

[@Dziricani]

There are 2 oxygen sensors (upstream & downstream). Did you replace the other one?

[@dragonstripes]

@@Dziricani yes, both were replaced.

[@kalomeon]

Emissions test?

[@dps67]

Can a cat be bad, but NOT throw a code?

[@felixrivera1568]

I speak fluently English but I can’t understand some of your language I think it’s something with inlet or outlet but I’m not sure what you’re trying to say..😩

[@rodneyspence7441]

What he's saying is that because the chemical reaction inside the catalytic converter occurs at very high temperature, the exhaust gas coming out of the converter (the outlet) should be hotter than the exhaust gas going into the converter (the inlet) if the converter is working properly. But if the temperature at the outlet is less than the temperature at the inlet, this indicates a problem with the converter. He said that a good converter will have an outlet temperature at least 10% higher than the inlet temperature - otherwise it indicates a bad converter. Hope this helps.

[@jaimizzygaming3368]

@@rodneyspence7441it helped me 😅

[@nolankarat5169]

Chris must be a Newfie

[@LemurMonitors]

We are all! Our head office is on Topsoil road! BlueDriver is born and breed Islander!

[@nolankarat5169]

@@LemurMonitors Yes by didn't know that, makes the videos even better!