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Threads Tagged with
po421
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Warm Up Catalyst Efficiency P0421, P0431
Euge82
on 03-15-2013
09-16-2014
10:10 AM
by
ppgoal
6
24,773
Audi A6
2002 A4 3.0 Quattro DTC P0421/P0431
AnthonyVas79
on 03-17-2012
04-08-2012
11:48 PM
by
aquariumjunky
2
8,240
B6 Models
P0241: Warm Up Catalyst Efficiency Below Threshold
mogwai88
on 03-31-2012
03-31-2012
12:09 PM
by
bigdadi
1
11,051
Audi A6
How to fix the problem coming up with the code P0431
sixcoco
on 01-25-2012
02-13-2012
02:51 PM
by
Rolling Blackout
8
12,726
Audi A4
CEL: Code P0421
(
1
2
3
...
Last Page
)
saintforlife
on 07-24-2007
10-26-2011
08:57 PM
by
igortiger
61
77,814
Audi A6
help p0421 cat code what to do?
ratherb1
on 05-03-2011
05-03-2011
11:31 AM
by
ratherb1
0
5,261
Audi A6
'00 B5 S4 with P0421
the24thletter
on 04-16-2011
04-16-2011
02:08 PM
by
the24thletter
0
3,992
S Car Model Line
P0421 on a 2002 3.0 V6 Fwd, what to do ?
ScGiants28
on 02-09-2011
02-09-2011
11:49 PM
by
ScGiants28
0
2,206
B6 Models
PO241 Diagnostic Code
psanta
on 07-22-2010
08-05-2010
05:31 PM
by
psanta
2
4,177
B6 Models
P0156... sometime after P0421
alex jb
on 05-19-2010
05-20-2010
11:26 AM
by
hxgaser
2
3,156
Audi A6
Can the p0421 code really be connected to a vac. leak??
(
1
2
)
cacaro
on 10-20-2009
01-08-2010
03:34 PM
by
cacaro
18
4,383
S Car Model Line
02 Audi A4 3.0 Quarttro for sale
707782y
on 01-02-2010
01-04-2010
02:57 AM
by
707782y
1
1,454
Archive - Vehicles for Sale
Oxygen (02) Senor replacement - preferred brand?
(
1
2
)
j_dinan
on 07-27-2009
07-28-2009
12:50 AM
by
hxgaser
12
1,977
Audi A6
check engine light from fuel sys cleaner ??
(
1
2
3
)
graybno
on 01-31-2009
02-12-2009
08:41 AM
by
padog
29
7,749
Audi A6
P0421 error 1 Cat or 2?
Madtown
on 09-03-2008
01-14-2009
09:00 PM
by
5th_year_senior
2
1,485
General Tech
fault codes po421 and po431
simsaudi3.0
on 02-02-2008
03-12-2008
11:37 PM
by
tj19855
7
8,930
B6 Models
MOVED: fault codes po421 and po431
simsaudi3.0
on 02-06-2008
02-06-2008
09:57 PM
by
simsaudi3.0
0
1,861
Audi A4
Code p0421
typhoonfd
on 11-23-2007
11-23-2007
10:00 AM
by
typhoonfd
4
1,852
S Car Model Line
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