P0421 diag. code????
#1
06-05-2005, 12:53 PM
P0421 diag. code????
Hey Everybody,
I am new to the forum and have a question if any knows the answer. My 02' just displayed a p0421 diag. code as a result of the check engine light. the consensus up till this point via other research sources is that the error is in fact just that an error (i.e. totally erroneous) in fact most sources state the the error is the result of a malfunction in the check engine light system. I hoped maybe someone in this forum has had the same problem and maybe some insight. Thanks.
I am new to the forum and have a question if any knows the answer. My 02' just displayed a p0421 diag. code as a result of the check engine light. the consensus up till this point via other research sources is that the error is in fact just that an error (i.e. totally erroneous) in fact most sources state the the error is the result of a malfunction in the check engine light system. I hoped maybe someone in this forum has had the same problem and maybe some insight. Thanks.
#2
07-01-2005, 02:05 PM
RE: P0421 diag. code????
I have an '02 Mitsubishi Lancer. I just got the Service Engine Soon light for the first time after 95,000 miles. I went to AutoZone and the code was P0421. Which translates to:
Warm-up catalyst below threshold Bank 1
I was told it is probably not a big deal, but I should get some fuel injector cleaner. I've actually never used that stuff so it would probably be a good idea anyway. He said there's a remote possibility that I might need a new oxygen sensor ($300), but that's not likely.
Also:
I'm not sure how reliable it is but this site:
http://www.mitsubishisucks.com/cars/...er/lancer.html
says there's a service bulletin:
2002 Mitsubishi LANCER 02 - Other Fuel > FUEL SYSTEM, OTHER [Part 090000 ]
TSB No: 89 Replacement: NHTSA ID: , December 01, 2002
Summary: malfunction indicator lamp (mil) on and diagnostic trouble code (dtc) p0421. *tt
Warm-up catalyst below threshold Bank 1
I was told it is probably not a big deal, but I should get some fuel injector cleaner. I've actually never used that stuff so it would probably be a good idea anyway. He said there's a remote possibility that I might need a new oxygen sensor ($300), but that's not likely.
Also:
I'm not sure how reliable it is but this site:
http://www.mitsubishisucks.com/cars/...er/lancer.html
says there's a service bulletin:
2002 Mitsubishi LANCER 02 - Other Fuel > FUEL SYSTEM, OTHER [Part 090000 ]
TSB No: 89 Replacement: NHTSA ID: , December 01, 2002
Summary: malfunction indicator lamp (mil) on and diagnostic trouble code (dtc) p0421. *tt
#3
12-11-2005, 08:44 PM
RE: P0421 diag. code????
ORIGINAL: HydroGuy
Hey Everybody,
I am new to the forum and have a question if any knows the answer. My 02' just displayed a p0421 diag. code as a result of the check engine light. the consensus up till this point via other research sources is that the error is in fact just that an error (i.e. totally erroneous) in fact most sources state the the error is the result of a malfunction in the check engine light system. I hoped maybe someone in this forum has had the same problem and maybe some insight. Thanks.
Hey Everybody,
I am new to the forum and have a question if any knows the answer. My 02' just displayed a p0421 diag. code as a result of the check engine light. the consensus up till this point via other research sources is that the error is in fact just that an error (i.e. totally erroneous) in fact most sources state the the error is the result of a malfunction in the check engine light system. I hoped maybe someone in this forum has had the same problem and maybe some insight. Thanks.
* If you need your check engine light turned off, unplug your battery for 10 minutes, then re-connect it. (This resets your car's computer)
Laters,
-Jonny_Doce-
#4
12-26-2005, 01:35 PM
RE: P0421 diag. code????
makin a long story short...i had the same 421 code...its the cat. recall. did u ever get the recall work fixed? if not congrats you get a new cat 4 free. if they already did it, u havta bitch and bitch some more to get it fixed, but theyll do it. i work at mitsu and have seen every lancer in town come in...verry common prob dood
#5
02-25-2006, 06:00 PM
RE: P0421 diag. code????
update..they extended the recall form lancers up to 100,000 miles, if u havnt done it yet get it done cuz theyre on factory backorder and the wait is a bitch
#6
02-28-2006, 11:32 PM
RE: P0421 diag. code????
ORIGINAL: jonny_doce
If i was you, i would go to Autozone and see what they say. They check it for free. One time my engine light was coming on along with my car acting up. I had it checked, and was told that it was an ignition problem. I had a hunch that it was one of my coils, because i had new plugs and wires at the time. Heres how i found out which coil it was.....the diagnostic first told me that one of the cylinders was having a failure (One of the cylinders that has the coil on it) so what i did, is reset my computer, and then swapped coils from one side to the other. I reved up my engine so the check engine light comes on, and took it back To autozone. they said that its the other cylinder acting up this time. (the other cylander with the coil on it......so, thats how i knew that it was the coil that was messing up, and which coil that it was) Currently I already replaced both coils, so i dont know if this is a common problem that lancers have.
* If you need your check engine light turned off, unplug your battery for 10 minutes, then re-connect it. (This resets your car's computer)
Laters,
-Jonny_Doce-
If i was you, i would go to Autozone and see what they say. They check it for free. One time my engine light was coming on along with my car acting up. I had it checked, and was told that it was an ignition problem. I had a hunch that it was one of my coils, because i had new plugs and wires at the time. Heres how i found out which coil it was.....the diagnostic first told me that one of the cylinders was having a failure (One of the cylinders that has the coil on it) so what i did, is reset my computer, and then swapped coils from one side to the other. I reved up my engine so the check engine light comes on, and took it back To autozone. they said that its the other cylinder acting up this time. (the other cylander with the coil on it......so, thats how i knew that it was the coil that was messing up, and which coil that it was) Currently I already replaced both coils, so i dont know if this is a common problem that lancers have.
* If you need your check engine light turned off, unplug your battery for 10 minutes, then re-connect it. (This resets your car's computer)
Laters,
-Jonny_Doce-
did you use original Mitsubishi Coilpacks?
or did you use aftermarket coilpacks?
the reason that I ask is because we have some problems getting Mitsubishi coilpacks in Trinidad
#7
01-20-2007, 11:14 PM
RE: P0421 diag. code????
Hello all. I have an 03 Oz edition, and the check engine light just went on at around 68,000 miles. I have yet to take it to Auto Zone to see what code is the problem, but if it is the P0421, where can I find the catalytic recall info online? I've been checking, but have not had any luck yet. Also, are there any symptoms that this problem is happening? We've been smelling burning at times, and also sometimes the sulfur smell of a bad cat.
