P0420 on 2004 rx330

[STL_G8GT]

2004 rx330. Had oil consumption issues when we bought it at 170k. I piston soaked it, cleaned valve covers, timing belt, etc. purrs pretty well now, stopped the consumption. Running Valvoline Restore and Protect 5w30. Does smell like exhaust / rich at idle on start.

There was a pending p0420 code yesterday. I hooked up a scan tool and unfortunately BOTH rear o2s are switching when the car is revd to ~2k.

I also think there's a small exhaust leak or two up front. The donut gasket fitting after the Y has some soot on the bottom, and I can smell exhaust at the drivers door.

I thinking of buying some used 2006 highlander cat/manifolds from a local salvage yard and re-gasketing everything forward of the Y. Manifolds are ~120$ each and are grade A used. 2006 did represent the cutoff to the better PCV system and less oil consumption.

The alternative is 4x the $ (walker or eastern - in Colorado I have to buy the carb compliant ones because of politicians), or Lexus OEM $800 each. Other option would be 02 spacers, and I really am not crazy about it, I would like to get rid of the fuel smell.

Ltfts are 4% / 9%.

 

[GSCJR]

Buy once, cry once. I've never liked aftermarket

 

[slacktide_bitog]

If there is a leak before the cat, especially if it's before the last oxygen sensor, address that first. If you don't get another manifold or Y or whatever, try JB Weld muffler cement. If the cement holds up and the code doesn't come back, you saved yourself lots of money

If the code goes away, but the cement doesn't hold up, then replace the Y/manifold.

Make sure the manifold you get is from a 3MZ, unless Toyota used the same exhaust on the 2GR (unlikely). Toyota switched to the 2GR around that time 2006

If you live in an emissions county and you're for inspection soon, go now while the light is still off

 

[D60]

I'm guessing he's not in an emissions county based on talk of spacers.

Friends with mailing address in neighboring state?

I didn't realize JYs could sell used cats. I mean, great if they can but I thought it was illegal.

 

[STL_G8GT]

I'm guessing he's not in an emissions county based on talk of spacers.

Friends with mailing address in neighboring state?

I didn't realize JYs could sell used cats. I mean, great if they can but I thought it was illegal.

This is an interesting thought, but they are all one unit. I guess I should clarify what the place that they wouldn't cut the cat off...

 

[STL_G8GT]

If there is a leak before the cat, especially if it's before the last oxygen sensor, address that first. If you don't get another manifold or Y or whatever, try JB Weld muffler cement. If the cement holds up and the code doesn't come back, you saved yourself lots of money

If the code goes away, but the cement doesn't hold up, then replace the Y/manifold.

Make sure the manifold you get is from a 3MZ, unless Toyota used the same exhaust on the 2GR (unlikely). Toyota switched to the 2GR around that time 2006

If you live in an emissions county and you're for inspection soon, go now while the light is still off

The issue I'm running into is because of the way the engine is mounted it's going to be a real pain to get to that rear manifold. So if I get in there to change the manifold gasket I really only want to be in and out of there one time. It's such a crazy design you can't see the entirety of the amanifold anyway, so I don't know that I would be able to confirm that there was a leak from that gasket itself. I suppose I could smoke it from the tail pipe and then watch in the engine bay...