Torque

Forums

Forums

Guest  

Show or hide header
Welcome Guest, posting in this forum require registration.




Torque » Torque OBD ECU Scanner » Torque Discussion / Ideas » P0420 tid cid

Pages: [1]
Author Topic: P0420 tid cid
agentu008
Member
Posts: 2
Post P0420 tid cid
on: June 4, 2018 (GMT)

I habe a 2007 chevrolet aveo 1.4 16v and yesterday the mil light came on with p0420 error and tid cid test failed with min 77 current 52. What does that mean? Is the cat or o2 sensors?

F-150Torqued
Member
Posts: 436
Post Re: P0420 tid cid
on: June 5, 2018 (GMT)

Catalyst efficiency monitor routines run continuously in the Powertrain Control Module. Catalyst efficiency is determined by some weighted algorithm based on a number of factors over a certain length of time. I am uncertain about specifics, and trigger points are different depending on whether exhaust uses a single CAT or dual CATs or ‘Y’ pipe with single CAT.

But your code is triggered when the O2 switching ‘RATIO’ (in percentage) of the front O2 sensor as compared to the rear O2 sensor exceeds a factory minimum spec (77%) for YOUR exhaust configuration. Your current ratio (at instant of Mode 06 test) was 52%. IN OTHER WORDS, your rear O2 sensor was switching approximately once for every two times the front O2 registered a voltage switch. That equals P0420

I would trust your O2 sensor. It did what it is supposed to. Switched when oxygen level around it changed. If they are bad, they tend to get ‘lazy’ and don’t switch as actively as they should.

Cure any misfires. Check your fuel trims (Short Term and Long Term). Make sure it is not running rich or the CAT is not getting ‘swamping’ with unburned fuel. Otherwise – you probably are looking at replacing the Catalytic Convertor.

——————–

54371019

agentu008
Member
Posts: 2
Post Re: P0420 tid cid
on: June 6, 2018 (GMT)

Thanks for your answer!


This a chart for fuel trims at idle…. Looks right?

Pages: [1]
WP-Forum by: Fredrik Fahlstad, Version: 2.4
Page loaded in: 0.076 seconds.

  Follow me on twitter