Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

07 Omega Catalyst system efficiency below threshold

Anthonie

Member
Joined
Apr 21, 2020
Messages
61
Reaction score
3
Points
8
Age
22
Location
Melbourne
Members Ride
VE Omega
Hi all,
This morning I started the car for work and was immediately greeted with a check engine warning, after calling RACV to come scan it the code thrown was a P0420 Catalyst system efficiency below threshold bank 1... I am confused as to why this code was thrown as I have had a new exhaust fitted with new cats, I have the exhaust for nearly 3 weeks now and to date have had no problems until this morning, if someone could enlighten me as to how this is occurring I’d very well appreciate that
 

mechanic

Active Member
Joined
Aug 27, 2018
Messages
280
Reaction score
131
Points
43
Location
Australia
Members Ride
Commodore
Go for a decent freeway drive on cruise control. This system only self-tests under very specific conditions (I'm surprised it came up on cold startup).
Google catalyst monitor drive cycle for an example of how it needs to be tested.

Some of the reasons the catalyst monitor will fail are:
Poor quality converters
old or poisoned converters
air leaks in exhaust
sensor faults
 

Anthonie

Member
Joined
Apr 21, 2020
Messages
61
Reaction score
3
Points
8
Age
22
Location
Melbourne
Members Ride
VE Omega
Go for a decent freeway drive on cruise control. This system only self-tests under very specific conditions (I'm surprised it came up on cold startup).
Google catalyst monitor drive cycle for an example of how it needs to be tested.

Some of the reasons the catalyst monitor will fail are:
Poor quality converters
old or poisoned converters
air leaks in exhaust
sensor faults
I’m really hoping it’s just a sensor fault... the car is at the mechanics but after turning off the car and then letting it sit I went to turn it back on and there was no code so I drove it to my mechanic
 
Top