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Trouble Codes
P Codes (Powertrain)
P0400 - P0499
P0421
P CODES (POWERTRAIN) P0400 - P0499 P0421
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Found 22 results
Code P0421
I Have Already Replaced My Rear Catalytic Converter And Downstream O2 Sensor Along With Fixed Exhaust Leaks. Map Sensor And I Know I Have A...
Asked by
Robhaynes84
·
5 ANSWERS
6 IMAGES
2004
DODGE STRATUS
VIDEO
Is it Safe to Drive Check Engine Light?
Instructional repair video
GUIDE
Check Engine Light
Why is my check engine or service engine soon turned on? In this guide we talk about what this is associated with this notorious light, what it is used for and what you...
Codes P0421 And P0431
This Car Use Only 60,000km. And The Engine Check Light All Get On. The Fault Codes Are P0421 And P0431. We Suggested The Customer Use Some...
Asked by
pengrr5200
·
1 ANSWER
6 IMAGES
2009
PORSCHE CAYENNE
2006 Mitsubishi Galant Code P0421
Car Has Check Engine Light On. I Changed The Cat On The Bottom Of The Car But Still Has Light On. I Understand That It Can Be A O2 Sensor...
Asked by
Diaz764
·
9 ANSWERS
1 IMAGE
2006
MITSUBISHI GALANT
2001 Mazda MPV PO421 CODE
Engine Performance Problem 2001 Mazda Mpv 6 Cyl 141000 Miles My Car Tries To Start, Then Shuts Off After About 3 Seconds, I Keep...
Asked by
demetriswilson000
·
1 ANSWER
2001
MAZDA MPV
VIDEO
How to Read Trouble Codes
Instructional repair video
2000 Mitsubishi Galant OBD Code PO421
Obd Code Po421 Is Registering On My Car. According To What I'd Read It Means The "warm Up Catalyst Efficiency Is Below Threshold Bank 1...
Asked by
skykings44
·
7 ANSWERS
2000
MITSUBISHI GALANT
I Have One Confirmed P0421 Code And One Pending Code...
This Morning P0301 Code Pop Up In The Pending Code Category. I Have P0421 Code Which Is Related To Catalyst 1 Efficiency Below Threshold...
Asked by
vish4369
·
3 ANSWERS
1 IMAGE
2004
HYUNDAI SONATA
GUIDE
Check Engine Light Safe to Drive?
We are a team of ASE certified mechanics that have created this guide to help you understand if your car is safe to drive with the check engine or service engine soon...
2001 Hyundai Santa Fe OBD II Code P0421 Problem
I've Been Having Trouble With Code P0421. I Had The Catalytic Converter Replaced And It Went Away. Two Days Later The Check Engine Light...
Asked by
jorge10928
·
5 ANSWERS
2001
HYUNDAI SANTA FE
PO421
I Have A 2000 Montero Sport. Got Code Po421 And Have Sequentially Replaced All 4 O2 Sensors In Addition To Having A Complete Tuneup...
Asked by
quinny24
·
4 ANSWERS
1942
MITSUBISHI OTHER
Trouble Code P0421
I Have A Mazda 626.2001 4 Cyl. Auto. 76k. Check Engine Light Came On. Autozone Checked And Code P0421 Came On. The Counter Guy Suggested A...
Asked by
irish81449
·
3 ANSWERS
MAZDA 626
P0421 Code Please Help?
Hope Somebody Can Help Me With This One. The Check Engine Light Went On 3 Days After I Bought My Car From A Toyota Dealer. I Took It To The...
Asked by
wangnnfnn
·
2 ANSWERS
2005
MITSUBISHI LANCER
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