Question about 2003 Mitsubishi Lancer

1 Answer

My check engine light will not allow my car to get inspected. when I plug the computer in it says that it is a O2/cat failure. I have with in the last 10 days have had both cats replaced as well as both O2's replaced and im still getting the same reading. But when I plug it in everything is reading correctly both O2 sensors are reading in the range that they are suppose to. does anyone have any ideas on what could be going on?

Posted by on

  • lee_damiani Jul 21, 2009

    the codes have been cleared and they kept coming back on, but i believe that i have solved the problem, there is a tsb on the code and it requires a software update

  • lee_damiani Jul 21, 2009

    they have been cleared and they kept coming back on, i believe that i have fond the problem thugh. there is a tsb on the code that keeps coming up. so its a software fix in the cars cpu. the light is sending out the wrong error message

×

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Genius:

    An expert who has answered 1,000 questions.

  • Master
  • 1,071 Answers

Codes will need to be cleared they will not go out on their own then a readiness drive will need to be performed dealership should be able to tell you how to perform this step

Posted on Jul 21, 2009

  • paul campbell Jul 21, 2009

    software could definately be it

×

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
New users get to try the service completely Free afterwhich it costs $6 per call and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Engine light code po420?


Code 420 refers to the catalytic converter in the exhaust pipe.
The code means the engine computer things the cat is not working correctly based on the data coming from the O2 sensors.
The sensors and the cat would need to be inspected.

Nov 17, 2015 | Chrysler Pacifica Cars & Trucks

1 Answer

Check engine light is on. Code is showing P0420. What does this mean?


This code means the downstrean (behind) O2 sensor determines a reduced level of effectiveness in the cat. converter-it may not be 'lighting off' (600+ degrees) to burn any hydrocarbons left over from the combustion process. I can be that the cat is bad, or there is an exhaust leak before the cat, or the sensor itself is bad. You can do a visual inspection to determine if there is a leak, and use a scanner to see if the O2 sensor is working properly. It should read a fairly steady voltage and not switch nearly as fast as the upstream O2 sensor. The downstream O2 sensors only purpose is to monitor the cat-you might try clearing the Check Engine Light first to see if it comes back. Then you should consider contacting your dealer since you may be covered under an extended warranty that they have to put on emission devices.

Dec 24, 2010 | 2005 Dodge Grand Caravan

2 Answers

PO420 code-service engine light is on


P0420 Catalyst System Efficiency Below Threshold (Bank 1) first thing to do is go back to basics do a tune up (plugs) check the plug wires spray them with water or windex if you get a miss change them, run some fuel injector cleaner through it, don't just throw parts on it ,that is'nt cheap

Mar 24, 2010 | 2002 Nissan Altima

1 Answer

I have a 1996 saturn wagon. it failed on omissions for egr. ox sensor and catalyst. I had a new egr.. o2 sensor.. oxygen sesor before catalyst.. drove car on many different drive cycles and over 4-600...


You need to read the codes that your check engine light is showing. Go to Autozone or any place like that and they can read the codes for free. Throwing parts at a car doesn't fix it but finding the source of the problem and then repairing as necessary will allow for better results. Going off the check engine light being on can mean it is anything.

You have two O2 sensors on your car. One just after the head on the header. This is the O2 sensor that tells the PCM what the air/fuel is and the PCM can adjust accordingly. The one BEHIND the catalytic converter (or cat for short) does nothing but tell the PCM that the cat. is working properly. You may be changing the wrong O2 sensor. Also the EGR could be an electrical problem if that is the cause of the emissions failure.

So to review, find out the codes, post back with the codes and everything can go from there.

Feb 26, 2010 | 1996 Saturn SL

1 Answer

Engine light codes 02-3151 and P0420


Code P0420 is a code for Catalyst efficiency. The computer is seeing the post Catalytic converter o2 sensor having too much activity. The Cat. should be cleaning the exaust of Hc, co, and Nox. The post cat o2 will read the o2 content in the exhaust and if it moves up and down too much or to high and low, the computer interperates that as the cat not ridding the exhaust of it's pollutants. This indicates that the converter is unable to preform properly. The problem could be a bad cat, o2 sensor (Pre- and/or post cat)or o2 sensor wires, or an air fuel mixture problem that has caused the cat to fail. Many other engine operating system failures can cause the converter to not work properly.

Sep 10, 2009 | 2000 Toyota Corolla

1 Answer

Check Engine Lights On


if the code is for the rear cat o2 sensor i suggested to replace the cat. the rear o2 sensor is to tell the commputer ha good is the cats if the cat not burning the gas. the commputer need to see the o2 sensor to check the cat's

Apr 17, 2009 | 2000 Toyota Corolla

1 Answer

Just changed original cats with direct fit magnaflow


Some systems actually depend upon a certain amount of restriction in order to work properly. The additional flow in the new system will mess with factory set flow expectations. If one of the O2 sensor wires have not been moved and have burned onto an exhaust pipe, You can either ignore the light if it's running well, or take the next (expensive) step and install a programmable engine control unit. However, in many states the light being on will cause you to fail inspection.
If you want to retain the exhaust system, you also could put a reducer in the pipe behind the cat to slow down the exhaust flow. It would not give you the added mpg that an open system will, but may restore the O2 sensor operation and likely you will still have the same sound effect that the system produces. Have a fault scan done...if it shows O2 sensor failure, that's where to go.

Apr 08, 2009 | 2006 Pontiac GTO

1 Answer

In a Saturn SL2 1998, I have the check engine soon light on. The codes readings show P0133 and P0422.


P0133 is an oxygen sensor "response too slow" code (meaning it's not getting up to temperature quickly enough, and the computer is assuming damage to its heating element). P0422 is a catalytic converter problem indication (cat is below peak efficiency). It's assuming you have a failure with the primary O2 sensor and that the cat is also bad. Change your O2 sensor first, have the codes cleared, and see if the cat code comes back or if the O2 sensor change fixes both issues.

Jul 29, 2008 | Saturn SL2 Cars & Trucks

1 Answer

Catalytic convertor replacement on Mercedes Benz 430 ML


You could probably do this, but you're going to be running with a permanent check-engine light. The twin O2 sensors on each exhaust pipe are for emissions reasons. Your primary (pre-cat) O2 sensors help the engine determine how much fuel to inject, based on reading the level of unburned oxygen in the exhaust stream. Your secondary O2 sensors (post-cat) are there to provide a similar reading. The car's computer then compares these two values to determine the efficiency of the catalytic converters. If the comparison strays outside an accepted range, the computer trips a fault light.

If you have emissions testing or regulations to that effect where you live, you will not pass inspection. In addition, if you have smog laws that mandate cats and other smog equipment, you could be risking a huge fine if you're found to have removed them. I'd check with an auto parts store about getting some generic universal cats (make your choice based on the length of the cat assembly and the diameter of the inlet and outlet pipes). These are generally far less expensive and work just fine.

On a side note, are you positive that the cats are bad? If you're tripping a fault code for a failed cat, it could be that one or the other of the O2 sensors are bad and causing an indicated cat malfunction. I'd have at least a couple other places look at the car and see whether it's the cats or the secondary O2 sensors before shelling out the money for cat replacement.

Jul 21, 2008 | 2006 Mercedes-Benz ML-Class

Not finding what you are looking for?
2003 Mitsubishi Lancer Logo

167 people viewed this question

Ask a Question

Usually answered in minutes!

Top Mitsubishi Experts

yadayada
yadayada

Level 3 Expert

76630 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8499 Answers

Are you a Mitsubishi Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...