How is secondary air injection flow detected?
10-25-2006, 12:07 PM
#1
Audiworld Junior Member
Thread Starter
Join Date: Mar 2002
Posts: 79
Likes: 0
Received 0 Likes
on
0 Posts
How is secondary air injection flow detected?
Does anyone know how the ECU detects secondary air injection flow? Is it only via the o2 sensor or something else?
Thanks,
Thanks,
10-25-2006, 01:23 PM
#3
Triggered by Temp levels..>>
As determined by the post CAT O2 sensor..
Activation is mean't to provide a hotter charge and burn off the higher Carbon monoxide and hydrocarbon levels needed at cold start (through a richer Mix)
Activation is mean't to provide a hotter charge and burn off the higher Carbon monoxide and hydrocarbon levels needed at cold start (through a richer Mix)
10-25-2006, 04:51 PM
#4
AudiWorld Super User
Join Date: Nov 2003
Posts: 2,006
Likes: 0
Received 0 Likes
on
0 Posts
I thought it runs for 65 sec on a cold start, only 5 sec on warm re-start (self-test)
It's purpose is to inject a bit of extra air into the system to help light off the catalytic converter when starting, to reduce start-up emissions. I think I read this somewhere in the Bentley, as my daughter has a potentially-bum secondary air pump on her 2000 A4 and so I was scouring the Bentley regarding it.
\_O_/ ~john
\_O_/ ~john
Thread
Thread Starter
Forum
Replies
Last Post
mobaar
A4 (B5 Platform) Discussion
4
07-15-2009 03:54 PM
airmax617
S4 / RS4 (B5 Platform) Discussion
2
12-09-2003 08:37 AM