Threads Tagged with p0421

A4 (B5 Platform) Discussion

02, 2000, 2002, 2004, a4, a6, audi, catalytic, code, converter, fault, p0421, quattro, s4, shows, vw

Code P0421 was NOT catalytic converter

dpeverhart on 02-24-2010

10-07-2014 11:30 AM
by Prospeeder

6

25,741

fixed 16805 P0421 with O2 extender

johnkk on 09-22-2013

09-22-2013 06:46 AM
by johnkk

0

2,485

2002, 2003, 30, a4, a6, audi, avk, b6, octane, oxygen, p0421, p042193, quattro, s4, sensor, v6, warranty

P0421 already replaced cat

Kombi03 on 02-05-2013

02-14-2013 03:58 PM
by 2000_A6_2.8_Avant

4

3,332

1995, 2001, 27, allroad, audi, coolant, cruiser, engine, land, p0421, sensor, start, temperature, turn, wont

Allroad Won't Start, Please Help

(

1 2)

mmasner on 02-06-2013

02-12-2013 06:22 PM
by mmasner

17

38,124

Audi allroad

02, 2002, 2004, 30, 30v, a4, audi, avk, b6, check, code, coils, engine, light, mileage, misfire, p0421, po421

P0421 and misfires 04 A4 3.0

blueskymine on 09-14-2012

09-20-2012 01:57 PM
by ct_esq

2

3,692

P0421 and Gas -- anyone had similar story?

a4avant99 on 05-25-2012

05-25-2012 10:56 AM
by 2.7Lturbo

7

2,191

audi, b5, catalytic, cel, clear, code, engine, error, intermittent, lacquer, laquer, p0421, p0431, s4, thinner

2001 S4, CEL/Catalytic Issues

yakavish on 03-21-2012

04-09-2012 03:16 PM
by yakavish

9

4,320

2002, 2004, audi, cat, denali, large, leak, p0421, p0431, p0455, pre, temp, warm, xl, yukon

Trouble getting through emissions testing

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1 2 3)

M4NB00B5 on 01-24-2012

01-26-2012 05:50 PM
by jcman

20

5,955

16805, 16815, 2000, a6, audi, bank, cat, catalyst, code, efficiency, low, p0421, p0431, quattro, treshold, trouble, warm

Fault codes:P0431,P0421,P1603-intermittent?

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1 2 3)

tmaslar on 01-20-2007

11-21-2011 11:52 AM
by 02ALLROAD02

24

47,098

VAG-COM Discussion

1996, 2001, 30, a4, a6, audi, code, forum, foulers, mazda, miata, p0421, plu, plug, plugs, replace, s4, spark

P0421, spark plug replaced, then ABS and ESP

a4avant99 on 11-06-2011

11-11-2011 01:48 PM
by a4avant99

8

5,070

2002, a4, a6, allroad, audi, audiworld, b6, code, codes, engine, log, o2, p0421, p0431, trouble

Codes P0421 and P0431

ShadowF on 08-13-2011

08-13-2011 03:31 PM
by ShadowF

0

4,911

30, allroad, audi, audiworld, catalic, catalytic, cheap, converter, fix, fixes, flash, forums, p0141, p0421, spacer

Catalytic Converter - Cheap Fix from Dealer

2002 allroad on 04-21-2011

07-08-2011 10:33 AM
by O2Allroad

7

19,972

2.7T V6 Discussion

APR fix vrs TSB fix at audi

(

1 2)

mikester2008 on 06-10-2011

06-14-2011 05:42 AM
by thejulex

10

1,977

Audi allroad

audi, blocks, car, constant, cylinder, failure, icm, intermittant, intermittent, make, measuring, misfire, miss, p0421, speed, vag

Miss while at constant speed

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1 2 3)

normohl on 05-09-2011

05-15-2011 05:54 PM
by EuroXS4

28

4,032

02, 2002, 2003, 30, a4, audi, catalytic, code, converter, exhaust, leak, p0421, quattro, vaccum, vacuum

p0421, yay (specific question)

(

1 2)

DZA on 03-21-2008

04-09-2011 07:59 PM
by theugly02

12

2,828

catalytic code

host23age on 11-19-2010

03-23-2011 01:56 PM
by ryan_qttro

3

3,343

30v V6 Discussion

02, 18t, 1999, 2002, 30, a4, a6, audi, bank, code, idle, ii, o2, obd, p0421, quattro, rough, sensor, warmed

B6 A4 or D2 A8?

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1 2 3)

A84Nate on 10-29-2010

11-19-2010 07:06 PM
by A84Nate

25

3,296

air, audi, injection, p0421, p1411, p1423, po421, s4, secondary

P0421 and other MILs

2000_A6_2.8_Avant on 11-19-2010

11-19-2010 04:54 PM
by 2000_A6_2.8_Avant

0

1,501

Codes??

jrc922 on 10-26-2010

10-28-2010 10:25 AM
by jrc922

5

1,947

16805, 2002, 30, a4, a6, audi, audy, code, codes, error, fault, list, message, p0421, quattro, vag

2002 Audi A6 Quattro Error Code Help

l_smith on 08-04-2010

08-06-2010 11:29 AM
by Dana @ Ross-Tech

3

3,552

VAG-COM Discussion

42, audi, bank1, catalitic, catalytic, catylic, codes, converter, convertor, ct, mechanic, miata, milford, p0421, p0431, reflash, return, weigh

Catalytic Converter Opinions - Please Weigh In

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1 2 3)

ilsaccente on 05-25-2010

05-28-2010 04:42 AM
by ilsaccente

23

5,291

2003, 27t, 30, a4, audi, b6, bad, bosch, coil, o2, p0421, recall, s4, sensor, sensors

P0421 May Just Be O2 Sensors

tecoya on 05-12-2010

05-14-2010 10:33 AM
by Pete@ECSTuning

4

2,092

2004, 27t, a6, audi, cat, clear, code, delete, engine, p0421, po421, replacement, s4

P0421 - Cat code

greenquattro on 05-01-2010

05-01-2010 06:34 PM
by VONBOTTLE

1

2,354

18t, audi, catalytic, catilac, conver, converter, efficiency, is, operating, p0421, precatalytic, primary, s4, threshold, warm

Pre or Primary Catalytic Converter Question

conall on 03-22-2010

03-24-2010 05:52 PM
by conall

1

1,272

01119, 01592, 02262, 16805, 17, 258j, 30l, 4b0, 962, a6, address, audi, code, fault, p0421, ross, tech, vag

vag-com code on my 02

PaJames on 02-26-2010

03-01-2010 04:07 PM
by PaJames

7

6,342

any way to tell if it has piggie pipes?

ucf_motorcycle on 02-15-2010

02-16-2010 04:44 AM
by SloopJohnB@mac.com

3

846

Need some advice on a sell vs. save decision

KneeDeep on 01-06-2010

02-13-2010 12:45 PM
by 01A6Turbo

8

1,446

2000, 2004, 27t, a6, audi, code, ecu, extend, flash, o2, p0421, piggy, pipes, po431, s4, sensors, tsb

New to A6 2.7t Few questions

Johann2.7t on 02-05-2010

02-05-2010 06:18 PM
by VONBOTTLE

3

1,466

17965, 2001, 2004, 2012357, 27, 27l, 4b0907551, a6, allroad, audi, catalytic, converter, p0421, p0431, tsb

Help with codes for 01 A6 2.7

tjscanlon on 12-29-2005

01-27-2010 05:14 PM
by leeststorm

5

1,647