How to check your catilytic converter

[GNRick]

Anybody ever try this?

YouTube - ‪How to check your vehicle's catalytic converter.‬‏

 

[RmvBfrFlght]

Anybody ever try this?

YouTube - ‪How to check your vehicle's catalytic converter.‬‏

Yes, although I used the O2 sensor mount point to connect the pressure gauge into the exhaust. Note that this was on a car that had the O2 (WB) right before the cat, not before the turbo.

RemoveBeforeFlight

 

[BRAD_PADGETT]

Why bother? In IL no emissions testing on our cars-Take the damm thing off your car. Brad

 

[GNRick]

I have an ATR "high flow cat" but sometimes people ask if their cat is plugged up and I never knew how to check one before. Maybe I'm just bored, I dunno.

 

[BlackBandit]

I use a broomstick to check cats. I take the cat off and shove it in one side and out the other. If there is anything in the way the cat is bad. Luckily repeating this test will fix any "issues".

 

[83ttypecooled]

Cats

Hi,
Besides the broomhandle "fix", there are alternatives.Some of us still have to pass an emissions test. Sooo... this one is cheap and easy,but does require one of the most basic diagnostic tools,a vacuum gauge. Hook said gauge into the fuel regulator hose. Disable the EGR valve by unplugging and capping it. Note the hot idle vacuum,then raise the engine off idle,let's say to about 2000 rpm. Ideally, vacuum should increase 3 to 5 inches of mercury. If this doesn't occur, there is an exhaust obstruction. Since the cat is the most restrictive element in the exhaust system,it is likely the cause of this restriction. By nature they are restrictive anyway,but a blocked cat will cause vacuum to drop down 5 or more inches of mercury.Symptoms of a blocked cat are black smoke and no power. Super rich fuel mixture.Try this,it is an oldschool diagnostic tool,but has worked good for me. Good luck with your trouble.

 

[ijames]

And to test for function get one of those infrared thermometers and go for at least a 20 minute drive to get the cat well warmed up. Park the car, leave it running in park, and reach under and check the temp of the inlet and exit of the cat. Should be at least 100F hotter at the exit if it is working. I think you need a thermometer that goes to 500 or 600F, but that's from memory, it may only be 400F at the exit.

 

[Roger]

Best test I've found is to look to see if a test pipe has been installed.

 

[Yankee John]

Question that may or may not be related- Will a plugged cat cause knock (or false knock)???

Reason I ask- My car is showing a lack of power and the other symptoms listed above, and my knock gauge shows knock under load, such as when I'm going up a hill or passing a slow car. I dont hear anything audibly though. When this happens, the Scanmaster usually shows between .5 to 3 degrees of retard.

I had a situation where I washed my car and SOMETHING got wet (I'm thinking it was my Translator). My car ran like crap and a LOT of gas got dumped into the exhaust. The converter got so hot that my carpet started smoking!!!

Im wondering if I killed my converter and it is causing knock gauge to go off and my ecm to retard the timing.....

Thanks in advance to any insight that you could provide!
John

 

[GW2]

Why bother? In IL no emissions testing on our cars-Take the damm thing off your car. Brad

Amen, I love hearing my turbo spool.