Quick and Easy Catalytic Converter Tests

[@robrichman3314]

so to be clear, if the O2 Sensor in the OBD2 for B1S2 and B2S2 (after cat sensors) are going up/down that is bad... we want the S2 to be around .6v, or more of a solid line. the S1 should be up/down.

[@asaadmanna6401]

Great explanation and thorough test. Thank you!

[@larrygibbons6489]

Excellent Instructional Video !!!

[@lawsonstallings1955]

Good job. Thank you.

[@smms5056]

AWESOME 👍👍

[@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 I drove with bad kat about a week but no engine light on and after I drove another week without Kat no engine light on . When I change my both Kat and drove 500km not engine light. Then I put fuel injector cleaner and drove another 150 km . And after engine light on and it says on my obd2 Kat defect.

[@humbledhands]

My pre caT sensor was showing over three volts? Any ideas?

[@bobreese4807]

I have an oil burning 2017 KIA with a 2.4 L that is going to get a new engine..BUT ,,,since it has 67K miles I am concerned about condition of CAT. I have a OBDlink MX+ scanner that indicates that O2 upstream sensor temp is 200 degress hotter than downstream O2 sensor. Also the graph of upstream sensor does not show but the downstream does but graph gets steady a little high. I have read so many times that the CAT out is hotter than input...if CAT is good.. Any ideas?

[@BobSmith-tn2qp]

As far as I know, upstream should be cooler then down stream. If the engine was removed, I'm sure the catalytic converter can he inspected for damage and carbon deposits inside the honeycomb

[@dangatto8666]

I don't have a fancy monitor but my temperature laser shows 440 degrees coming in to the converter and the same coming out. No lights are on on the dash, but I have no power going uphill. Is my cat bad? 2003 Frontier.

[@borkganza9627]

Yes it’s probably plugged.

[@thaflame8424]

Can this make it overheat

[@Z-Ack]

Yes and can cause buildup of soot on the valves which in turn could cause a variety of issues. But yea, imagine you shoved a potato in the exhaust pipe, a cooked potato so its mushy and allows some air to fart past.. thats what a clogged catl is like.. clogged... usually the exhsust will stink funny like an actual cat fart. Where you cant tell what the smell really is but have the hunch... lol

[@quantass]

Still amuses me these KZbin video titles. "Quick & Easy" but then go on to use an out of reach $5000 tool for the diagnosis.

[@rayprill2883]

You can get a temperature gun (less fancy than this one, but just fine) for $25. Likewise, you can get a simple OBDII reader like a Veepeak for $25 which can simply graph the O2 sensor. Both tools are enormously useful and well worth having, especially if you have older cars. The temp gun comes in handy elsewhere, like grilling, or plumbing, etc.

[@Z-Ack]

Jesus.. no if the cat on the motor side is say 400° and the side closer to the muffler is 450 or 475 then you have a clogged cat.. that means its heating up from the blockage. Should be cooler on the otherside.. and the rare metals in the catalytic material reacts with various hydrocarbons produced by the burning fuel which will actually make that honey comb material glow red like its burning stuff but is actually just a reaction where the rhodium, platinum and other metals are bonding with those various harmful hydrocarbons. There is still the exact same amount of carbon monoxide coming out of your tailpipe if you didnt have a cat.. you'll still die just as fast if subjected to it for too long in a closed environment.. but with a cat at least you wont be breathing trace amounts of noxious gasses like sulphur dioxide, nitric oxide, nitrogen sulphide and so on.