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Recent questions tagged p0421
0
like
0
dislike
0
answers
288
views
Failed smog check read error code P0421 but no check engine light.
asked
Dec 21, 2018
by
cdubg213
(
101
points)
obd-emissions-failed
mazda-6
smog
p0421
obd2
1
like
0
dislike
2
answers
275
views
What does Catalysis Bank 1 P0421 mean on a 2002 Audi A6 Quatro?
asked
Nov 16, 2018
by
anonymous
audi
quatro
p0421
0
like
0
dislike
1
answer
626
views
P0421 Mitsubishi -
asked
Oct 24, 2018
by
anonymous
p0421
code
0
like
0
dislike
1
answer
153
views
wP0421 Hyundai -where should I start?
asked
Oct 22, 2018
by
Dawn Michelle
p0421
cen-tech
code
1
like
0
dislike
2
answers
326
views
2004 Hyundai Santa Fe with engine codes P0304 and P0421, what is the meaning of the codes?
asked
Sep 26, 2018
by
anonymous
hyundai
santa-fe
p0304
p0421
0
like
0
dislike
0
answers
306
views
P0431 Audi -
asked
Aug 3, 2018
by
Will
p0431
p0421
p491
p492
0
like
0
dislike
1
answer
339
views
what do i need to do to get my car smogged ?.
asked
Jul 23, 2018
by
anonymous
2001
mazda
4-cyl
p0421
626
0
like
0
dislike
1
answer
459
views
Will gasoline additives or cleaning O2 sensors help the Mitsi P0421 code problem?
asked
Jul 12, 2018
by
George Wagner
2006
mitsi
code
p0421
catalyst
0
like
0
dislike
1
answer
500
views
P0421 Mitsubishi - 2.4L intermittant
asked
Jun 29, 2018
by
Stu
p0421
catylst
efficency
below
threshold
0
like
0
dislike
1
answer
281
views
P0421 - mazda
asked
Jun 8, 2018
by
geoff
p0421
engine
0
like
0
dislike
1
answer
298
views
2002 VW New Beetle 1.8 t gas
asked
Jun 7, 2018
by
Tina
(
102
points)
p0411
p0421
1
like
0
dislike
2
answers
419
views
I have a 2001 Mazda Protege 2.0L with the engine codes P0131, P0421, & P0171
asked
May 31, 2018
by
anonymous
mazda
protege
p0131
p0421
p0171
0
like
0
dislike
1
answer
459
views
how to repair obd2 scanner code po421 on 2004 Mitsubishi lancer
asked
May 22, 2018
by
anonymous
code
dtc
p0421
0
like
0
dislike
1
answer
329
views
2006 Mitsubishi Lancer Oz rally P0421 fix
asked
May 1, 2018
by
Connor
code
p0421
0
like
0
dislike
1
answer
648
views
P0171,P0421 Mitsubishi -lancer es 2.4 what could trigger both of these codes
asked
Apr 27, 2018
by
powerhouse199216
code
p0421
p0171
0
like
0
dislike
1
answer
172
views
Any suggestions where to get a cheaper catalytic for '98 mitsubishi montero?
asked
Apr 16, 2018
by
jojo
code
p0421
0
like
0
dislike
1
answer
346
views
P0421 Mazda -
asked
Mar 24, 2018
by
sna
p0421
light
0
like
0
dislike
0
answers
248
views
how expensive is it to fix a P0069 for a 2005 mitsubishi Eclipse
asked
Mar 16, 2018
by
anonymous
code
p0421
p0069
0
like
0
dislike
1
answer
219
views
P0431 Mitsubishi -
asked
Feb 15, 2018
by
Tony
po431
p0421
0
like
0
dislike
1
answer
351
views
I have the po431, and po421 codes showing on my reader.
asked
Jan 3, 2018
by
anonymous
p0421
po431
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