P0420...Max Gods, What do I do?
Originally Posted by Maxima-Ness
So...is there a TSB for the 02-03 models with a P0420?
Originally Posted by MIXXMAX
Not sure about the '02-'03 models, but there is a bulletin for the '00-'01's with California emmissions. It covers up to 8yr/80K. In fact, I just started a thread on this a couple of days ago because I just got mine done at the dealer. They re-programmed the ECU and all is good!
Originally Posted by Maxima-Ness
Well, I just went throught the whole fiasco with Nissan about the p1147 issue, which I got covered under warranty. ECU reprogram and update were performed. Now it throws a P0420 code, and im not sure if its a ghost code or if its the real thing. I had it cleared and now Im just waiting to see if it comes back. I'll call around on Tuesday and see if I can get my hands on a TSB. Hopefully someone has one already and is kind enough to post it here... 

Originally Posted by IceY2K1
That's the one behind the main cat.
Otherwise, it could be:
6)spark plug<~~depends on mileage
7
Otherwise, it could be:
6)spark plug<~~depends on mileage
7
Ice, sorry to dig this from the buried, but I was reading more about P-0430 (bank 2) and your post had this thing about the possibility of being related to the plugs.
Can you write some more about plugs and P-0430?
I just changed my plugs last week and know I am getting P-0430 and everyone is saying it is O2 sensor but I started to suspect it could be the plugs.
Thanks in advance!
BB
What does it do?
I seem to have what I think is the same problem at ya'll. But I was intrested to know what the maxs were doing. I need to get up and go last week and it reved up to 5rpms and stayed there. Now the thing is it was like I was in neutral and the car had no power so I let up a little....it gave me a small bump and then went. I gave it a little more gas and no power again but no bump this time. So I just got out of the way (in the slow lane) and just went normally. Know I drive 65miles one way to work and I have noticed that when I in regular highway speed the engine will neutal out (not the trans because i never feel a shift or the button for od off) the rpms stay the same but no power and the speed slightly goes down. We have taken it to The Muffler Shop and the said they tested the cats and they are bad. I question them afterchecking out some prices and a friend told me about this site. I have 126K all highway miles. I am not asking for a diag. but wondering if this is like what some of you experienced.
Originally Posted by KeithV
Great, my 2000 GLE is showing P0430 and P0420...
completly stock, 105000 miles.
Is that all the o2 sensors?
completly stock, 105000 miles.
Is that all the o2 sensors?
I have the 0430 and it seems like it could be the O2s... there is a thread just about the same.... just find it...
Stealerships
Took My 01 Max to Woodfield Nissan tonight. I had Autozone pull the code before going to dealer. It had 2 codes stored. Both P0420. Car has 79,400 miles. Woodfield quoted $ 1,500.00 to fix. I quote, "replace front tube, O2 sendor and ECM update". I told them to forget it. Paid the friggin $ 107.00 diagnostic fee and got the hell out of there. They wash all the cars coming out of service. Most expensive car wash I've ever had.
I'm going to try Nissan corporate after I e-mail the Jack*** general Manager @ Woodfield. I know car sales are slow but this is BS service.
I'm going to try Nissan corporate after I e-mail the Jack*** general Manager @ Woodfield. I know car sales are slow but this is BS service.
i did get this code a couple of months ago...it stayed on for about a month..now i think my cat is gone bad...because of the bad smell i've been noticing (according to guys on here). So i'll just get a straight pipe and 02 simulator...
Originally Posted by Bborges
Shouldnt that STILL be under warranty?
Originally Posted by BeaSE01
My car is still under 8/80 warranty. Dealer actually called me and told me to call Nissan about the problem. They told me they have been burned by Nissan in the past. They said they've done the prescribed fix and than had Nissan deny the claim. They said they're tired of being stuck for the repairs. I'm calling Monday AM and see what's going to happen.


its under warranty....
The moral of the story is ....
Start by taking a look at http://www.obd-codes.com/trouble_cod...old-bank-1.php
Then, as I am sure a number of people will attest to, the most common reason for this in a 2000 Maxima is a bad ignition coil. The 2000 Maxima had a problem in this area, and somewhere floating around there is even a class action suit about it.
As for fixing it, unfortunately Nissan in its infinite wisdom, does not have a code to tell you a coil is bad. It just tells you the catalytic converter is not functioning properly. So fixing it is kind of a crap shoot. You can buy two coils (left & right are different) and try to figure it out, but it is easier to just buy 6 new ones. I bought mine from nissanfanatic about a month ago, look under Group Deals> GD:Coil Packs. It cost me about $300 for all 6 which is a good price.
However, DO NOT WAIT. I DID, big mistake. My CEL has been on and off a bunch of times over the last 2 years, and I was not too worried about it. Finnaly, after my wife started hounding me to fix it, I finally installed 6 new coils. The CEL went off, for about 400 miles, then came on again. So I reset it, and about 40 miles later it came back on. Finally I gave up and sent my car to the dealer. It just cost me almost $1000 to replace my catalytic converter. What we (the dealer, my regular mechanic and I) think happened was the coils were not firing well enough and I waited so long that I plugged up the converter. Car now runs better than it has in a long time, like about 40,000 miles. Moral - Fix it now or pay the price.
Then, as I am sure a number of people will attest to, the most common reason for this in a 2000 Maxima is a bad ignition coil. The 2000 Maxima had a problem in this area, and somewhere floating around there is even a class action suit about it.
As for fixing it, unfortunately Nissan in its infinite wisdom, does not have a code to tell you a coil is bad. It just tells you the catalytic converter is not functioning properly. So fixing it is kind of a crap shoot. You can buy two coils (left & right are different) and try to figure it out, but it is easier to just buy 6 new ones. I bought mine from nissanfanatic about a month ago, look under Group Deals> GD:Coil Packs. It cost me about $300 for all 6 which is a good price.
However, DO NOT WAIT. I DID, big mistake. My CEL has been on and off a bunch of times over the last 2 years, and I was not too worried about it. Finnaly, after my wife started hounding me to fix it, I finally installed 6 new coils. The CEL went off, for about 400 miles, then came on again. So I reset it, and about 40 miles later it came back on. Finally I gave up and sent my car to the dealer. It just cost me almost $1000 to replace my catalytic converter. What we (the dealer, my regular mechanic and I) think happened was the coils were not firing well enough and I waited so long that I plugged up the converter. Car now runs better than it has in a long time, like about 40,000 miles. Moral - Fix it now or pay the price.
i got the CEL light last night and i went to autozone for the check. FREE BY THE WAY. and they told me it is a bad cat. However, i just put the y pipe and fast cat on so the sensor is goin nuts. dont know if anyone else is having the same issue with the same situation but i was told to drive the car like it was brand new and let the O2 relearn the stats of the cars vitals. Thats my P0420 story....
So for those of us that are over 80k throwing a p0420 what should we do? Will replacing the 02 sensor clear the code? Also, which sensor is the p0420...is it the one on the exhaust manifold found under the hood, or the one after the catalytic converter under the car?
Thanks in advance
Thanks in advance
p0420 codes
heres the skinny the p0420 codes are the "rear" o2 sensors, however you will need more info from the scan, it should tell you wich bank you will need to replace. ie bank 1 sensor 2 ect. putting in the new o2 sensor is in my opinion the way to go y bother dinking with the sim when u just unplug the o2 and thread the new one in. also are you having drivabilty probs? ? the bank 1 rear o2 is located downstream In the first "converter". the rear o2 bank 2 is located right in front of that flange where the front manifold bolts to the converter
Okay I have a 2000 maxima stock and we have replaced the coils and plugs. The SES light has been coming on and off every once in awhile so it came back on yesterday and we took it to autozone and it ran one code of P0420 Bank 1. Can someone help me out, Ive read into some of the threads and Im not things it the coils but I would like everyones else opinon. The car has 135,000 and it runs strong but once in awhile when sitting still in park or drive it will just cut off....PLEASE HELP!
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
P0420 code is for the three-way cat. That's right bank 1. It is covered under 80K miles federal warranty, so if you have less then 80K then go to the dealer and do it for free. The dealer will most likely insist on also putting in the O2 sensor per the TSB. The O2 sensor responsible for determining if the cat is bad is the one in the rear of that cat, so in this case rear B1 O2 sensor. The sensor screws in under car behind the cat and its harness is under the hood. There could be as many as 4 of these so you need to know which one. I don't know why you would put in a new O2 sensor, it's not listed as th cause for P0420. I heard that it helps but I wonder if only temporarily... There could be many causes but in all likelyhood it's the cat.
NOTE: This tip is for all Nissan and Infiniti models except '00-'01 Maxima/I30 P0420 incidents.
Service Information: Catalyst locations are not so obvious in later vehicles due to the integration of catalysts into exhaust manifolds and exhaust front tubes in some later models. There can be up to 4 catalysts in V-6 engines and 2 catalysts in 4 cyl engines. It is important to identify the correct catalyst when replacing a catalyst to resolve a P0420/P0430 incident. The most reliable method to find the correct catalyst location is by the fact that it will always be in-between the front and rear oxygen sensors of the incident bank. For P0420 the bank-1 front O2 sensor will have a black harness and the rear O2 sensor will have a white harness. For P0430 the bank-2 front O2 sensor will have a blue harness and the rear O2 sensor will have a white or gray harness.
IF YOU CONFIRM:
An applied vehicle has the following symptoms:
· MIL 'ON' with DTC P0420 stored
AND
· Vehicle runs OK and does NOT have a misfire or driveability incident
ACTIONS:
1. Confirm this bulletin applies to the vehicle you're working on. Refer to the Repair Flow Chart on page 3 for details.
2. Compare the current ECM part number to Chart A on page 5.
· If your ECM part number is listed in Chart A, reprogram the ECM to the latest ECM data. See ECM REPROGRAMMING on page 6 for details. Do NOT replace any parts in this case.
· If your ECM part number is NOT listed in Chart A, you do not have to reprogram the ECM. But you will have to replace the Front Tube Assembly and the Front
H02S1-B1 Oxygen Sensor. The reason you replace the o2 is because it affects the catalyst function.
Service Information: Catalyst locations are not so obvious in later vehicles due to the integration of catalysts into exhaust manifolds and exhaust front tubes in some later models. There can be up to 4 catalysts in V-6 engines and 2 catalysts in 4 cyl engines. It is important to identify the correct catalyst when replacing a catalyst to resolve a P0420/P0430 incident. The most reliable method to find the correct catalyst location is by the fact that it will always be in-between the front and rear oxygen sensors of the incident bank. For P0420 the bank-1 front O2 sensor will have a black harness and the rear O2 sensor will have a white harness. For P0430 the bank-2 front O2 sensor will have a blue harness and the rear O2 sensor will have a white or gray harness.
IF YOU CONFIRM:
An applied vehicle has the following symptoms:
· MIL 'ON' with DTC P0420 stored
AND
· Vehicle runs OK and does NOT have a misfire or driveability incident
ACTIONS:
1. Confirm this bulletin applies to the vehicle you're working on. Refer to the Repair Flow Chart on page 3 for details.
2. Compare the current ECM part number to Chart A on page 5.
· If your ECM part number is listed in Chart A, reprogram the ECM to the latest ECM data. See ECM REPROGRAMMING on page 6 for details. Do NOT replace any parts in this case.
· If your ECM part number is NOT listed in Chart A, you do not have to reprogram the ECM. But you will have to replace the Front Tube Assembly and the Front
H02S1-B1 Oxygen Sensor. The reason you replace the o2 is because it affects the catalyst function.
I believe i may need a MAF.
I was hoping you could assist me.
I've experienced multiple issues over last 4 months.
long story short, i've replaced all 3 cats. No ecm reprogram yet.
replaced spark plugs(bosch platinum).
i experience loss of power, hesitation and/or studdering while trying to accelerate. knocking while trying to hard accelerate.(i use premium gas)
after extensive reading... it comes down to MAF, IGNITION COIL(S) AND/OR ECM REPROGRAM.
Am i even close? what do u recommend at this point.
thanks for any help u can offer.
ps. no SES light now. did have it b4 which led to rplcng cats.
I was hoping you could assist me.
I've experienced multiple issues over last 4 months.
long story short, i've replaced all 3 cats. No ecm reprogram yet.
replaced spark plugs(bosch platinum).
i experience loss of power, hesitation and/or studdering while trying to accelerate. knocking while trying to hard accelerate.(i use premium gas)
after extensive reading... it comes down to MAF, IGNITION COIL(S) AND/OR ECM REPROGRAM.
Am i even close? what do u recommend at this point.
thanks for any help u can offer.
ps. no SES light now. did have it b4 which led to rplcng cats.
Originally Posted by swetcountrygrl
Okay I have a 2000 maxima stock and we have replaced the coils and plugs. The SES light has been coming on and off every once in awhile so it came back on yesterday and we took it to autozone and it ran one code of P0420 Bank 1. Can someone help me out, Ive read into some of the threads and Im not things it the coils but I would like everyones else opinon. The car has 135,000 and it runs strong but once in awhile when sitting still in park or drive it will just cut off....PLEASE HELP!
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
Can anyone help on this...I know what the manuel says it is but I need some help as of where to start. Thanks you!
Again, there are other problems that could cause a p0420. If you're getting it along with front o2 sensor errors, you've got to get that fixed before you know if you truly have a cat problem. That's something I just went through and it turned out I had no problem with the cat.
Any problem that causes the engine to run rich (misfire, injector, intake, timing) will throw a p0420.
Any problem that causes the engine to run rich (misfire, injector, intake, timing) will throw a p0420.
need advice
i need help with my '00 max. 4 months ago (121000 mil at that time now is 125000) i have the code PO430 "Catalyst Efficency Below Threshold (Bank two)" and i replace the cat (i don't know if that one is called pre-cat but the shape look like ice cone and is located behind the radiator), 2 oxygen sensors (the harness colors are white and red), new MAF + reprogram and perform injector cleaner service, with stealer-ship which is cost me over $2100 + with stupid tax(8.65)
. since then i have no code at all. But yesterday i drove. suddenly it came out SES light. i took to the auto zone and it pulled code PO420 "Catalyst Efficency Below Threshold (Bank One)"
. i explained to the autozone guy and he recommend me to change the rest of the o2 sensors.
Do you guys have any idea besides replace the rest of o2 sensors?. where is the main cat located and the pre-cat?. where is the BANK ONE and BANK TWO? is that any possible happen to the same cat? 'cause mine have warranty 1 year or 12000 miles. i was thinking to change the rest of the cat which i haven't change at all (consider from my milage and the lousy previous owner). where i can get the original nissan's cat but cheaper than stealer-ship. i don't wanna spend for diagnosis fee, 'cause basicly they gonna tell me the same thing from what i thought. before that, i wanna say thank you
. since then i have no code at all. But yesterday i drove. suddenly it came out SES light. i took to the auto zone and it pulled code PO420 "Catalyst Efficency Below Threshold (Bank One)"
. i explained to the autozone guy and he recommend me to change the rest of the o2 sensors. Do you guys have any idea besides replace the rest of o2 sensors?. where is the main cat located and the pre-cat?. where is the BANK ONE and BANK TWO? is that any possible happen to the same cat? 'cause mine have warranty 1 year or 12000 miles. i was thinking to change the rest of the cat which i haven't change at all (consider from my milage and the lousy previous owner). where i can get the original nissan's cat but cheaper than stealer-ship. i don't wanna spend for diagnosis fee, 'cause basicly they gonna tell me the same thing from what i thought. before that, i wanna say thank you
Originally Posted by DanL
If you have a California emissions Max and the code is P0420 (I'm assuming you've had the code pulled at AutoZone or elsewhere) then THIS TSB applies. Don't worry...you still have 20K miles before it runs out if the code was indeed P0420. Otherwise, chances are it was probably for something only covered for 3/36 anyway.
Originally Posted by swetcountrygrl
Okay I have a 2000 maxima stock and we have replaced the coils and plugs. The SES light has been coming on and off every once in awhile so it came back on yesterday and we took it to autozone and it ran one code of P0420 Bank 1. Can someone help me out, Ive read into some of the threads and Im not things it the coils but I would like everyones else opinon. The car has 135,000 and it runs strong but once in awhile when sitting still in park or drive it will just cut off....PLEASE HELP!
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
Thanks alot
I was looking into getting a new o2..but which one is it??
http://shop.nissanpartstore.com/buy....1&make_code=NI
Okay can someone please, please help me with this. I have ran the car a few months without fixing her and now she is really starting to cut off on me alot. Where should I start? Please anyones help!!!
Originally Posted by swetcountrygrl
Okay can someone please, please help me with this. I have ran the car a few months without fixing her and now she is really starting to cut off on me alot. Where should I start? Please anyones help!!!
If i was you, i would do reflash to the MAF or change it (consider it's cheaper than 02-03 MAF). and if it still coming on try to change the O2 sensors. u can get the parts from Dave B ( he has the cheapest price i've ever known)
Originally Posted by SoulEater
i need help with my '00 max. 4 months ago (121000 mil at that time now is 125000) i have the code PO430 "Catalyst Efficency Below Threshold (Bank two)" and i replace the cat (i don't know if that one is called pre-cat but the shape look like ice cone and is located behind the radiator), 2 oxygen sensors (the harness colors are white and red), new MAF + reprogram and perform injector cleaner service, with stealer-ship which is cost me over $2100 + with stupid tax(8.65)
. since then i have no code at all. But yesterday i drove. suddenly it came out SES light. i took to the auto zone and it pulled code PO420 "Catalyst Efficency Below Threshold (Bank One)"
. i explained to the autozone guy and he recommend me to change the rest of the o2 sensors.
Do you guys have any idea besides replace the rest of o2 sensors?. where is the main cat located and the pre-cat?. where is the BANK ONE and BANK TWO? is that any possible happen to the same cat? 'cause mine have warranty 1 year or 12000 miles. i was thinking to change the rest of the cat which i haven't change at all (consider from my milage and the lousy previous owner). where i can get the original nissan's cat but cheaper than stealer-ship. i don't wanna spend for diagnosis fee, 'cause basicly they gonna tell me the same thing from what i thought. before that, i wanna say thank you
. since then i have no code at all. But yesterday i drove. suddenly it came out SES light. i took to the auto zone and it pulled code PO420 "Catalyst Efficency Below Threshold (Bank One)"
. i explained to the autozone guy and he recommend me to change the rest of the o2 sensors. Do you guys have any idea besides replace the rest of o2 sensors?. where is the main cat located and the pre-cat?. where is the BANK ONE and BANK TWO? is that any possible happen to the same cat? 'cause mine have warranty 1 year or 12000 miles. i was thinking to change the rest of the cat which i haven't change at all (consider from my milage and the lousy previous owner). where i can get the original nissan's cat but cheaper than stealer-ship. i don't wanna spend for diagnosis fee, 'cause basicly they gonna tell me the same thing from what i thought. before that, i wanna say thank you
Ok, I just got back from the dealer. 2k1 @ 55k miles
"Check car customer says that service engine light stays on when driving
Performed systems test fault P0420 tech inspect car found converter ok (needs ECM reprogrammed and fuel system cleaned out) customer declined repairs at this time."
The guy said this isn’t covered under warranty and said the bulletin that I printed out doesn’t mean anything, it’s just tells the mechanic how to fix it. I also mentioned the 8/80k and he said it wasn’t covered. He pretty much laughed at me.
Now what, I'm already spent $115 for them to check my car? He said it would be about $400 something total (minus the $115).
"Check car customer says that service engine light stays on when driving
Performed systems test fault P0420 tech inspect car found converter ok (needs ECM reprogrammed and fuel system cleaned out) customer declined repairs at this time."
The guy said this isn’t covered under warranty and said the bulletin that I printed out doesn’t mean anything, it’s just tells the mechanic how to fix it. I also mentioned the 8/80k and he said it wasn’t covered. He pretty much laughed at me.
Now what, I'm already spent $115 for them to check my car? He said it would be about $400 something total (minus the $115).
Originally Posted by BlackFlux
Ok, I just got back from the dealer. 2k1 @ 55k miles
"Check car customer says that service engine light stays on when driving
Performed systems test fault P0420 tech inspect car found converter ok (needs ECM reprogrammed and fuel system cleaned out) customer declined repairs at this time."
The guy said this isn’t covered under warranty and said the bulletin that I printed out doesn’t mean anything, it’s just tells the mechanic how to fix it. I also mentioned the 8/80k and he said it wasn’t covered. He pretty much laughed at me.
Now what, I'm already spent $115 for them to check my car? He said it would be about $400 something total (minus the $115).
"Check car customer says that service engine light stays on when driving
Performed systems test fault P0420 tech inspect car found converter ok (needs ECM reprogrammed and fuel system cleaned out) customer declined repairs at this time."
The guy said this isn’t covered under warranty and said the bulletin that I printed out doesn’t mean anything, it’s just tells the mechanic how to fix it. I also mentioned the 8/80k and he said it wasn’t covered. He pretty much laughed at me.
Now what, I'm already spent $115 for them to check my car? He said it would be about $400 something total (minus the $115).




