Mitsubishi Montero & Montero Sport This sport utility vehicle offers more size than the other Mitsubishi SUVs, but manages to keep a sporty look and comfortable feel, unlike many larger SUVs.

Montero XLS Catalytic Code P0431

  #21  
Old 01-13-2015, 10:22 AM
2001Mitch3.5XS's Avatar
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I had the same problem ad the cataclean worked very well for me...just sayn
 
  #22  
Old 01-20-2015, 11:57 AM
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Default Code P0430 vs P0431

My 2004 Montero service engine light went on over the weekend and it is showing P0430, not P0431, yet I'm being told it is the catalytic converter Bank 2 (I think that is the driver's side). Going to try Cataclean, for sure, but just curious what the difference is between the 430 code and the 431 code.

Car has 107,000 miles on it. I bought it six months ago with 104K on it.

Recently replaced the air cleaner, which was filthy. Had a new timing belt put on before I brought it home from the dealer in July. I'm guessing it needs new spark plugs and wires, though it runs really well.

Anyone know the difference in the codes?

Thanks!
 
  #23  
Old 01-20-2015, 11:09 PM
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P0430 and P0431 are both Bank 2 Cat efficiency below threshold. Mitsubishi book does not list P0430. I wonder if different code readers produce slightly different outputs. Still - same problem.
BTW, followed up on a suggestion for the O2 spacers. It seem to actually work. Only after drilling out the spark plug nonfouler and assembling the unit I realized how this works. I must admit it is a pretty genius trick. I hope it will keep my check engine light off for now. Thanks for advice.
 
  #24  
Old 01-22-2015, 09:31 AM
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Just sayn here the CATACLEAN did actually work for me...
Put a full bottle in with a 1/2 tank of gas and went up interstate 81. Not sayn that I was speeding or anything ( cause that doesn't happen) like that but I blew the **** out of it. I got a lot of little bits of junk out of it.
 
  #25  
Old 07-09-2016, 10:42 PM
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Default How did you space out sensors?

Hi

Is there a blog on how to do it?


QUOTE=Ironchef2014;306587]No need for any electric work. The cheap way to bypass this code is to space


out both of the post cat oxygen sensors. The codes are due to the rear sensors indicating to the ECU that the readings are too dirty. By spacing them out of the exhaust stream a bit, the signal is cleaner, code is gone. Total cost: $8-$20.[/QUOTE]
 
  #26  
Old 07-27-2016, 05:39 PM
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Originally Posted by HunterD
P0430 and P0431 are both Bank 2 Cat efficiency below threshold. Mitsubishi book does not list P0430. I wonder if different code readers produce slightly different outputs. Still - same problem.
BTW, followed up on a suggestion for the O2 spacers. It seem to actually work. Only after drilling out the spark plug nonfouler and assembling the unit I realized how this works. I must admit it is a pretty genius trick. I hope it will keep my check engine light off for now. Thanks for advice.
Can you explain this drilling out of the anti-fouler please?
 
  #27  
Old 07-27-2016, 07:00 PM
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Sure thing. The Spark Plug Non-foulers are spacers which have both male and female threads of the same size as the spark plug. The spacer is a tube that is closed off on the engine side and has only a small hole in it to let gasses go in. So, in theory, if you have an old engine that burns oil, installing a spark plug with this non-fouler reduces the chance that oil will get splashed onto the electrode thus fouling the plug. As it happens, these non-foulers have the same thread diameter as the O2 sensor. Unlike the spark plug, O2 sensor extends pretty far past the thread, so you have to drill out one of the non-foulers with a drill bit of the same size as its internal diameter and then use them in a stack: intact non-fouler + drilled non-fouler + O2 sensor. You install this assembly into O2 bung hole and you are done.
I had cat converter codes thrown awhile back and installed these on both downstream O2 sensors. The codes never came back (after 15k miles).
Here is the link to the thread I followed for instructions:
How To: Install An O2 Sensor Non Fouler to Eliminate a Chek Engine Light with Pics - Chevrolet Colorado & GMC Canyon Forum
 
  #28  
Old 08-01-2016, 11:27 AM
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Been there, actually I have a thread about this...Anyways, don't know if mentioned, but here is what I did. First of all, Rock Auto has a replacement cat "y"" for less than $300.00, and shipping to PR was $50.00, I guess much cheaper in the lower 49 states.

What I did, was buy four (4) spark plug extenders at Autozone (Hunter mentioned it), they are sold at any auto parts, two (2) per downstream O2 sensor. Then with a good quality 1/2" drill bit for metal, I drilled two (2) of the extenders, and threaded one of the drilled extenders to a non drilled extender, then threaded the O2 sensor to the extender assembly. By doing this your sensor is away from the exhaust gas flow, but close enough to perform as intended. Uninstalled the cat "y" assembly from underneath the SUV, an easy task, you just need extensions for your ratchet tool, as to be able to reach the manifold to cat pipe nuts, undo a few bolts below the SUV, and the cat assembly comes down rather easy. If you don't want to do it yourself, take the assembly to a muffler shop, and have them empty the cats. I am lucky that I have a friend with a muffler shop, and he only charged me $10.00 for emptying them. Put everything back together in reverse order. The downstream O2 sensors will seem like they will be very close to the transmission, but don't worry, they will not touch the trans or be affected. Before doing all this, you should have unplugged your battery, so when you finish and connect it back on the codes will have erased. The code for cat issues will not come back, in my case it has been 6 months now, working flawless, and it is a relief not seeing the Check Engine Light (CEL) on for so long.

My SUV's gas mileage went up, power went up, CEL turned off, it sound rather nice, and it passed gas emissions inspection without a hitch.

Note: You also have to unscrew from the cat "y" assembly the upstream O2 sensors, but not mods are needed. Just unplug and unscrew, then when finished screw back and plug in. This job will take you about 1-2 hours, depending on your level of expertise. Also, I am not 100% sure if the spark non-fouler I used is the one I linked or a longer one. I purchased two (2) different lengths, then mix and match according to what I needed. You don't drill the non-fouler that screws to the exhaust pipe, as to widen the bypass hole, you leave as is.
 

Last edited by guangui; 08-01-2016 at 11:33 AM.
  #29  
Old 03-14-2017, 07:33 AM
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Default P0431, Mitsi Montero XLS (2001) and the non-foulers

I bought the non-foulers and they came in the mail yesterday. I have not crawled under the Montero yet - I figured I would do it this weekend.

As I understand it, I need four. Drill two out with 1/2 inch drill and screw each one into an undrilled one. This is done to accomodate the O2 sensor. Now I have two piggyback assemblies.

Then I screw an assembly into one of the holes where I unscrewed the 02 sensors, and screw the 02 sensors into the assemblies. And that should be the extent of this "repair".

I read DO NOT clean the O2 sensor or use any threading sealer, etc, on the sensors.

Does anyone know how long this is going to take, or any other advice that anyone has for me? I'm a mechanical guy - definitely not an idiot. But I'm not the guy that can remove my engine and rebuild it, either.

Wish me luck. All advice welcome.
 
  #30  
Old 03-14-2017, 12:03 PM
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Originally Posted by tdennehy
I bought the non-foulers and they came in the mail yesterday. I have not crawled under the Montero yet - I figured I would do it this weekend.

As I understand it, I need four. Drill two out with 1/2 inch drill and screw each one into an undrilled one. This is done to accomodate the O2 sensor. Now I have two piggyback assemblies.

Then I screw an assembly into one of the holes where I unscrewed the 02 sensors, and screw the 02 sensors into the assemblies. And that should be the extent of this "repair".

I read DO NOT clean the O2 sensor or use any threading sealer, etc, on the sensors.

Does anyone know how long this is going to take, or any other advice that anyone has for me? I'm a mechanical guy - definitely not an idiot. But I'm not the guy that can remove my engine and rebuild it, either.

Wish me luck. All advice welcome.
You are on the right track with the steps. Do not clean O2 sensors with anything. I found that it was easier to install O2 sensor into the non-foulers and then install the assembly into the exhaust pipe. One side (I think driver) will be a tight fit when you start (wire interfering a little), but once installed, there is plenty of clearance. I think you may even get away without disconnecting the wires from the harness.
 

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