Stalling issue

Hello fellow Tundra owners. So I have a 2006 Sr5 4.7 V8 double cab 2 WD. My truck randomly stalls. Not as much while driving although it occasionally randomly sputters. I’ve changed the plugs, coil packs, vacuum lines, MAF, among other items not related. I’ve cleaned the throttle body and reset ECM multiple times. I am at a loss. I’ve added catalytic cleaner and several injection system cleaners over the last few hundred miles. I thought at first it was possibly the Pedal Commander I installed so I’ve removed it and still having the same problem. It throws a PO420 code here and there as well as lean bank 1 & 2. I clear the codes and it runs fine for a bit. I may tackle the O2 sensors at the cats next. Any help would be appreciated. Thank you in advance.

 

PO420 (bank1/driver) and P0430 (bank2/passenger) are often a red herring for a bad upstream O2 sensor, and the stalling would jibe for that. Reason is simple: One of your two sensors is reading "off" incorrectly and it's likely lending to the ECM getting bad data, and therefore not able to get air/fuel ratio correct.

But O2 sensors are one of those things where you should (1) never use anything except the Denso/OEM brand 'exact fit' part for your truck versus any other brand, and (2) always replace the upstream and downstream as pairs to avoid future codes.

You can look up the exact-fit (i.e. non-universal) part at www.densoautoparts.com for numbers. DO NOT order O2 sensors from anyone with unverified supply chain, i.e. avoid scAmazon, fleaBay, WallyWorld, etc. RockAuto and Summit Racing are legit alternatives and often cheaper than any of those.

You gave enough info I could look it up pretty fast in their system, here's your numbers:

(This could also be the fuel pump faltering, which is another "make sure you use Denso brand" item. It could also be that someone did a timing belt change recently and didn't tuck away the crankshaft position sensor harness fully, so it's getting nicked by the belt/pulley. And the P0420/0430 codes can also be a variety of other things, which others have recently resolved with O2 spacers/foulers, but they lacked the stumbling/hesitation issues, which suggest fuel trim/fuel delivery component)

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