How to Check for a Bad or Stopped Up Catalytic Converter

Drilling a small hole and checking for pressure can quickly identify a bad or stopped up catalytic converter. Drill the hole upstream or in front of the cat and use a low pressure gauge. Often, a fuel pressure/vacuum gauge does the trick. You shouldn't have more than 1.5 -2 psi or so of pressure. Thanks for watching!

[stickittheman]

Thanks for your help seriously!!! Did this test on my 2003 trailblazer and got a solid 3.5-4 PSI after the converter using the 15 dollar pressure tester from harbor freight. The 2002 and 2003 trailblazers I guess are notorious for getting clogged converters and I definitely get some bogging under load like climbing a hill or accelerating at low RPM basically anytime I need torque from the engine. I also hear a pretty aggressive rattle coming from the converter which I can reproduce by rapidly tapping it with a rubber hammer so something definitely broke off and is rattling around in there restricting flow. Glad this video was here cause they are not cheap so I needed an airtight diagnosis on this one didn't want to flush 200 down the toilet!

[kazen]

Just did this test on my 2007 explorer and the drivers side cat was def clogged. I had removed the 02 sensor and tried to drive it and did not notice a power increase. I grabbed the same gauge from harbor freight and drilled the hole in front of the cat. The passenger side was fine and the drivers bounced all over. Thanks for the video this has been driving me nuts for weeks.

[jamestrevarthen]

Perfect info for my stopped up cat problem, preciate it!

[prollystoned]

Thank you for the description 🙏🏻🙏🏻🙏🏻 you answered my question no one else did

[stevenshelley]

Great video, I'm smelling something like burned clutch in my 97 ford f'-150 5.4 V8 RWD could that be my converters ? Great video thanks for SHARING 👍🙄

[castledomeknives]

Off to find a pressure guage...THANKS 👍

[darwingrose]

Great video, good way of checking catalytic converter, thanks very much

[paquesepas]

Great explanation. When you have 2 catalytic converters, what data should I look for to find the more suspicious one? Also is this more accurate than a laser temperature pointing after and before method?

[thatsallfolks]

Can this be why I get, Reduced Engine Power in my 06 Silverado?

[ChrisGrazioli]

Cadillac Converter? Is that because there's a tiny little Cadillac inside converting all those exhaust gases?

[passingthetorch]

So too much pressure tells you which side is bad?

[peppytrabonco]

I have the smelly sulfur smell and white smoke from exhaust. I also have 210 compression from cylinder 6. Are they both related or do I have to do valve clearances and clean my cat converter?

[petermelnyk]

Anyone have any videos of what the motor sounds like when the cats are will clogged cats cause a misfire in the cylinders?

[johnbunnjovi]

Could you also have pulled the O2 sensor and measured the pressure from there?

[johncano]

When it’s bad does the exhaust have like a bad egg smell?

[brendathornlimb]

How many catalytic does a 2004 chev trailblazer 4.2 straight 6 have

[octane]

Hey im in okc and need help how do i get ahold of you

[bobbiinfield]

My car has plain water dripping out exhaust joints on passenger side leaving a puddle and it’s idling a little low I checked fluid seem all fine I’m worried

[JimmySmall-cd]

Drill the hole at the front or the back of the

[Khaled-ifxs]

If catalyst clogged
How do check by scanner launch