Toyota Tundra Forums banner
1 - 5 of 5 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter · #1 ·
I have a 2001 with a p0420 code. Like said before I swapped the o2 sensors and still the came code I just dropped the cat and as a newbie to doing my own repair i have a "clean" pipe running into the cat but the pipes leading from the cat are full of black soot. would with warrent a new cat or is this how it should be. thanks for the info in advance.
 

·
Registered
Joined
·
609 Posts
I had a P0430 code on my 2003 Tundra recently. A few months ago (6 month 20K miles) I changed the front O2 sensor. Last week I got the P0430 code, had the shop re-set the computer, so far it did not come back. If your vehicle is running on and the inside of the cat did not break up, you maybe ok. My mechanic also said if the code comes back, we can remove the O2 sensors, put them back with a washer or spacer. This way the sensor is not that far into the pipe and the readings may change and be ok.
 

·
Registered
Joined
·
240 Posts
The computer compares activity of the front and rear oxygen sensors to check catalyst efficiency. The forward O2 (fuel control O2S) has a has a travel of > 800mV and < 200mV and switches very quickly <100ms. The rear O2S (cat montoring O2S) should have a very small range of movement on either side of 450mV and should switch slowly. If the two waveforms are similar (as if there is no cat or the cat is bad) then your code will set.

Did this code come out of nowhere? No rough running? Usually cats are killed by misfires (a MIL would be on) or extreme fuel system problems (MIL would be on). Have you had a check engine light on before?

PS stevekx your mechanic could get jail time for doing that, even though it's just a washer. Any kind of tampering to emission control systems is bad bad news.
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #4 ·
There has been no other code thrown in the time that we have owned it Feb 2010 we bought it used. i do not hear any air leak or really see anywhere on the manifold that would point to a blown gasket. while i had the cat off I blew air thought it and there did not seem to be an excess lose of pressure. so i do not think it was clogged. i am really thinking this is going to be a manifold replacement . but i am open to others ideas
 

·
Registered
Joined
·
202 Posts
When I had P0420 code and no other code, I replace my cat with aftermarket one and OEM sensors (two sensors) and MIL light didn't come back. So far I put 40K miles and climbing with aftermarket cat (driver side) and 2 OEM sensors. Then, I had P0430 and other code that I can't remember (related to O2 sensor). I replace the two sensors passenger side with OEM sensors. I put 10K miles and climbing, MIL didn't come back. Before all this cat and O2 sensors issues, I had a manifold leak, no code but my manifold leak is noticable (hearing). I replace my manifold with aftermarket ebay stainless steel headers.
 
1 - 5 of 5 Posts
Top