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AudiWorld Forums
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Threads Tagged with
p0421
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Threads Tagged with
p0421
Thread / Thread Starter
Last Post
Replies
Views
Forum
Need P0421 and P0420 ghetto fix - already STFU
Silver02A4Quattro
on Apr 6, 2007
Apr 8, 2007
03:27 PM
by
MM120
9
5,923
A4 (B6 Platform) Discussion
Opinion need - O2 Sensor & Combi Air Valves
plova
on Feb 5, 2007
Feb 6, 2007
04:35 AM
by
4Driver4
3
1,143
A6 / S6 (C5 Platform) Discussion
P0421,P0431 Cat Efficiency Codes with APR software
(
1
2
)
tmaslar
on Jan 21, 2007
Jan 24, 2007
06:54 PM
by
Jason @ Streetwerke
12
3,809
S4 / RS4 (B5 Platform) Discussion
Newbie Question: P0431 CEL Code
87ninefiveone
on Jan 19, 2007
Jan 21, 2007
07:00 AM
by
87ninefiveone
9
718
S4 / RS4 (B5 Platform) Discussion
P0421/16805: Warm up catalyst efficiency below threshold, bank 1...
PSUEng
on Jan 19, 2007
Jan 21, 2007
06:59 AM
by
87ninefiveone
3
2,573
S4 / RS4 (B5 Platform) Discussion
Fault codes from VAG scan...16805, 16815, 00716, 00962. Anyone seen/have these before?
SilverSchwinn
on Nov 19, 2006
Nov 20, 2006
07:04 PM
by
SilverSchwinn
8
17,188
A4 (B6 Platform) Discussion
Smog question for those using AWE Stage3 kits with APR downpipes.
Quattrosaurus
on Oct 3, 2006
Oct 3, 2006
08:21 AM
by
Marcus Frost
6
390
SoCal Discussion
Multiple Codes p0300, p0421 and p0431
WillyumYum
on Jun 20, 2006
Jun 20, 2006
11:42 AM
by
WillyumYum
2
1,635
A6 / S6 (C5 Platform) Discussion
Replaced Spark plugs. .Now getting Misfires code ... !!
(
1
2
)
Diavan
on Jun 17, 2006
Jun 18, 2006
03:40 PM
by
erik9108
11
1,263
S4 / RS4 (B5 Platform) Discussion
For those of you with the infamous catalyst error/CEL...
snowcat
on May 17, 2006
May 18, 2006
06:28 AM
by
Edd W
8
4,042
A6 / S6 (C5 Platform) Discussion
P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)
Object
on Nov 29, 2005
Nov 30, 2005
07:01 AM
by
RedWing
6
10,002
S4 / RS4 (B5 Platform) Discussion
P0421 Diagnosis
Kev 3.0
on Oct 25, 2005
Oct 25, 2005
11:04 AM
by
akula-ssh
2
501
A4 (B6 Platform) Discussion
P0421 code for O2 sensor
Kev 3.0
on Oct 24, 2005
Oct 25, 2005
09:38 AM
by
Kev 3.0
8
4,068
A4 (B6 Platform) Discussion
Can somebody explain this emission/cat question for me?
(
1
2
)
slimmn
on Aug 19, 2005
Aug 19, 2005
12:36 PM
by
6ULDV8
15
1,101
A6 / S6 (C5 Platform) Discussion
Cat problem - actually code P0421
geauxfaster
on Aug 18, 2005
Aug 19, 2005
11:55 AM
by
geauxfaster
7
1,053
A6 / S6 (C5 Platform) Discussion
emission test question ....P0421....please read...tx
audi2.7audi
on Jun 14, 2005
Jun 14, 2005
09:52 AM
by
4Driver4
4
926
A6 / S6 (C5 Platform) Discussion
2001 TSBs
glidar
on Jun 14, 2005
Jun 14, 2005
09:23 AM
by
glidar
0
753
Audi allroad
2000 2.7T. CEL Code 16805 P0421
ecgarzone
on Mar 12, 2005
Mar 16, 2005
02:12 PM
by
ecgarzone
2
1,364
VAG-COM Discussion
Emissions testing failure in WI w/ GIAC X
(
1
2
)
Juggernaut
on Jan 31, 2005
Jan 31, 2005
06:20 PM
by
Mike2kS4
13
569
S4 / RS4 (B5 Platform) Discussion
Anyone had their computer reprogrammed for CEL code P0421 or P0431?
atikovi@excite.com
on Sep 30, 2004
Oct 1, 2004
06:49 PM
by
steve l
7
1,263
Audi allroad
Again, CEL on 2 days later= what should I do guys? P0421
(
1
2
)
MDIAU
on May 27, 2004
May 27, 2004
04:12 PM
by
mpwolf
10
590
S4 / RS4 (B5 Platform) Discussion
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