Exhaust leakage testing -- looking for advice

[westslope]

Had Eastern Cats installed by the dealer in late October. Drove home with something not quite right as the Emissions Readiness s/DTC screen in Torque Pro showed no O2 connection even if the A/F and O2 sensors gave readings. LTFTs seem to work OK. About a week later, I had a P2A03 Pending fault code for Bank 2, Sensor 1.

Among other things, I want to check the exhaust system for leaks. It has been suggested that I could hook up and tape a ShopVac to the exhaust when the engine is cold, run it and spray potential leaking areas on the exhaust system with soap and water.

Is there any reason why this method should not work or why I should avoid it or be very careful if using it?

 

[Zack.]

Not sure about that method - what I did was hold a piece of tube to my ear and the other end near where the different exhaust parts meet with the truck running, until I heard like a repetitive puffing type sound. Careful not to touch the hot exhaust if you go this route.

 

[xyoverland]

I saw the positive pressure/soap water method in a Chris Fix YouTube video and was planning trying it myself.

 

[jsexton]

You can usually see leaks pretty easy when the engine is cold and it’s cold outside. Start it and crawl under.

 

[westslope]

You can usually see leaks pretty easy when the engine is cold and it’s cold outside. Start it and crawl under.

Oh so not wanting to do that during the wintertime!

 

[jsexton]

the weld on the header flange cracks sometimes and causes a leak there. Other than that, the 3 flanges on each side around the cats are the most likely places it would be leaking.

 

[XterraRising]

Yeah, so you’re basically pressurizing the exhaust system. You could also use a leaf blower as long as it will fit over the pipe. Then spray soapy water on your exhaust manifolds and work your way back. Wherever you see bubbles, that’s your leak.

 

[westslope]

I saw the positive pressure/soap water method in a Chris Fix YouTube video and was planning trying it myself.

Thanks! I watched two of Chris Fix's videos and found both helpful.

How to Find and Repair Exhaust Leaks EASY (Without a Welder)

How to Repair an Exhaust Leak DIY (No Welding)

 

[westslope]

Update:

Switched out the NTK A/F ratio sensor for a Bosch A/F sensor Bank 2, Sensor one. Looked like the shop did not put on anti-seize when it replaced it after putting in the new catalytic converters.

Then I taped a ShopVac pipe to the exhaust pipe with duct tape. Red Green would have been proud.

Gotta a buddy to turn it on and off as I scuttled around on a creeper, spraying soapy water on the flange connections and other connections. There were several leaks, especially on the passenger side. Usually close to gaskets. One bolt top was leaking on the driver side. One pipe connection had only one U-bolt. That was leaking like crazy.

I will try to take some photos but the gaskets look paper thin to me and I wonder if thicker gaskets would make a tighter seal easier to accomplish.

Take this to a shop or try to fix it myself? (I am not going back to the dealership.)

 

[TheCrabby1]

Update:

Switched out the NTK A/F ratio sensor for a Bosch A/F sensor Bank 2, Sensor one. Looked like the shop did not put on anti-seize when it replaced it after putting in the new catalytic converters.

Then I taped a ShopVac pipe to the exhaust pipe with duct tape. Red Green would have been proud.

Gotta a buddy to turn it on and off as I scuttled around on a creeper, spraying soapy water on the flange connections and other connections. There were several leaks, especially on the passenger side. Usually close to gaskets. One bolt top was leaking on the driver side. One pipe connection had only one U-bolt. That was leaking like crazy.

I will try to take some photos but the gaskets look paper thin to me and I wonder if thicker gaskets would make a tighter seal easier to accomplish.

Take this to a shop or try to fix it myself? (I am not going back to the dealership.)

I think ffxcores had some exhaust issue's with his new set up and replaced/doubled up or found heavy duty gasket's somewhere .

 

[xyoverland]

I think ffxcores had some exhaust issue's with his new set up and replaced/doubled up or found heavy duty gasket's somewhere .

Yeah the stock/OEM gasket was about the thinnest piece of copper you can make. The OEM replacement part was multi-ply and tapered towards the studs. Huge difference.

 

[Zack.]

Also if it’s leaking where the secondaries attach to the exhaust you can get a universal (labeled mopar I think) Remflex gasket that crushes up to like 50% to seal any gaps.

 

[jsexton]

Ahh, the red green show. That was great.