Excessive Exhaust Backpressure Testing

[jbadenoch]

I read about a lot of techs removing 02s or cutting exhaust to identify if exhaust(cat) is plugged. I use a back pressure tester, drill 1/8 inch hole and insert probe and rev eng, works every time. If not plugged then put an 1/8 inch rivit in hole. Bob in sc

[ricmorin]

My tester screws directly into the O2 port so there's no holes needed. Just had one today with over 8psi at idle. Wow.

[Tim Martin]

Are we insinuating that the old method of using a vacuum gauge and slowly increasing the engine rpms is not reliable or trustworthy? That's usually what I do and I have found it to be fairly consistent with the tester that I also have that threads into the O2 Sensor port.

[ricmorin]

Are we insinuating that the old method of using a vacuum gauge and slowly increasing the engine rpms is not reliable or trustworthy? That's usually what I do and I have found it to be fairly consistent with the tester that I also have that threads into the O2 Sensor port.

Of course those methods are still used, but what happens when you have twin cats on a v engine? Which one is it? I prefer a direct read for confirmation. It's a 5 minute test to confirm your suspicions. I hate being wrong.

[Tim Martin]

Are we insinuating that the old method of using a vacuum gauge and slowly increasing the engine rpms is not reliable or trustworthy? That's usually what I do and I have found it to be fairly consistent with the tester that I also have that threads into the O2 Sensor port.

Of course those methods are still used, but what happens when you have twin cats on a v engine? Which one is it? I prefer a direct read for confirmation. It's a 5 minute test to confirm your suspicions. I hate being wrong.

Hey. You are proposing great ideas and I admit that I had not thought of a dual cat system even though I have tested them already as well. That is the value of this forum - to share ideas from all sides. I guess I am still old school stuff and even though I work mainly on current vehicles I still find myself tending to think by the things we did through the years.

[protraxrptr17]

I love my gauge. It can screw into an o2 port or it has an air hammer attachment to punch a hole in the pipe and some self tapping screws.

[ricmorin]

I have the OTC one. Love it!

OTC

OTC-7215.jpg (5.13 KiB) Viewed 5424 times

[Tim Martin]

There's times it would be nice to have a longer hose between adapter and gauge.

[ricmorin]

Yeah, it's about 3-4 feet long. Never seems long enough. LOL! But it's a nice braided steel hose.

[brianp87]

I poke a hole and weld it. had a ford van plugged cat yesterday