Found out why P0420, P0430

^^^ This is a solid observation. A "lazy" sensor can send different signals. Just yesterday I replaced a "lazy" sensor that would drop randomly then "reactivate" on a 2004 Infinity M45. Having a solid OBDII Diagnostic Tool with realtime data acquisition surely helps identify strange issues.

 

Just hooked up to the ecu and said nothing was pending or stored. Only been 20-30 miles though so we will see over the next couple days. I just set a new dashboard and strip chart parameters in my obd software to monitor O2 voltage and temperature to play with tomorrow.

 

You are headed down the correct path my friend! Goodluck!

 

Thanks

 

If they don't come on by 40 - 50 miles, then I bet it is fine.

 

My Taco had a very small head gasket leak... the only way we knew for sure was with a coolant pressure test. Even with that, it took about 7 hours before i could see coolant in the cylinder. my coolant never changed color, but the resivior needed filling about once a week, and the coolant had a faint exhaust smell. The truck went to the shop at 175k with a misfire code, that was the first evidence this was happening.

Not that this is your problem, but def something to watch for!

 

My reservoir level has never moved from when I got it. Been 4 days now and just had it on the highway yesterday. Distance was 70 miles running around 70-75 mph and did great. So far no sign of the dreaded orange light.

 

Well traded my taco in today. Just wanted to post in here about the exhaust. In 5 months I probaby put a few thousand miles on it and the Magnaflow manifolds and rear cats held up great. No sign of any check engine light and I expect the stainless steel to look good for many years.

 

Did the truck feel any different after the Magnaflows went on? 3 to 1 vs that single bank that Toyota decided was a good idea. May have needed a full cat-back to feel a difference, but just curious.

 

It did but mostly due to the fact that the stock parts were in such bad shape and with the new parts the engine could breathe.

 

Did you put on the rear Magnaflow cats with pipes? I am curious how they directed the pipes?

 

Just cut out the old ones from the y and welded the new ones in.

 

Non CARB compliant. Aaaaaaah