Sequoia catalytic convertor

[naturalbornmudder]

2001 Toyota Sequoia popping a check engine light periodically throwing a code that reveals emissions out of spec for bank 1 after the catalytic convertor.
Ran a reference check for a legal replacement cat from our friendly neighborhood IM QA guy. Found the right replacement and picked it up for under $100. Replacement is 5 inches shorter than stock. Bought a couple of 2" ID to 2" OD exhaust fittings and we got it welded in ther in under an hour.

measures 1.916" OD on the rig. Length is 17"

2" I.D. to 2" O.D.(?)
Napa P/N 41944

Napa Catalytic convertor P/N 15140(1st choice)
or Napa P/N 15036

[naturalbornmudder]

new cat:
2.150" O.D.
2.080" I.D.
length 13 1/2"

[naturalbornmudder]

BUTTING THE EXISTING EXHAUST TO THE NEW CAT PIPE AND BUTT WELDING IT
looks like a desparagement of 3.5" in length. Difference of about .230" or 1/4" in pipe outside diameter(OD to OD).

SLIDING THE EXISTING EXHAUST INTO THE NEW CAT and FILLET WELDING IT
-I.D.(of new cat) to O.D.(of existing exhaust pipe) is about .060 or 1/16"

Fillet welding is preferred, and since 1/16" total is easy to overcome(think 1/2 of that measurement because of the floating wall so actually 1/32 or .032") Hell, you could even clamp it.

QUESTION: How do we overcome the 3.5" of missing exhaust pipe because the OEM cat was 3.5" longer than the new cat?

ANSWER: just pick up a piece of extension 2" ID to 2" OD and cut to length.

[naturalbornmudder]

note to be noted. The check engine light on the toyota was illuminated, which caused the ECM to turn off the vehicle skid control computer, which made that set of idiot lights come on as well. Once the new cat was installed, the ECM cleared the lights and the catalyst reset after 15 minuts or so of driving.

Another thing to be noted. Aftermarket cats are not nearly as efficient as their factory counterparts. The factory Toyota cat with 140K miles on it still filters better by a factor of 10 to 20 times than the brand new one we welded in. Both cats are well within spec, but it is surprising to note that aftermarket cats just seem to "get the job done" while the factory stuff is actually keeping the environment a little bit cleaner.