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Hi, my neon 2004, have the code: 0128,0551, 0420, 0622, 0517, 0563. I wanted to mention that it does not have catalyst, what could these codes mean?

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A real smorgasbord!
0420 is for the cat, so scrub that one. I could not find 0517-don't know what that means. 0551 and 0128 are sensor malfunctions, or circuit malfunctions for those two sensors (P/S pressure switch, and Coolant temp. sensor). Before going after that, take heed of 0622 and 0563: 0563 is system voltage too high, 0622 is generator field "F" control circuit malfunction. You have a bad voltage regulator in your alternator-putting out too much current. Try a different alternator-it may clear up the sensor malfunctrions, too.

Posted on Nov 30, 2012


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SOURCE: what is code 1494 mean for 2001 dodge neon

P1494 Leak Detection Pump Switch or Mechanical Fault
Part of the early evaporative emission system. (Fuel tank fumes)

It’s there to allow the computer to run an integrity test of the fuel tank, lines and carbon canister’s ability to contain all of the fumes coming from the tank and all line associated with the system.
The code could be set for a number of reasons such as a faulty gas cap, cracked vacuum lines, solenoids & vent valves stuck to the pump itself.
It can be a very difficult fault to cure being it doesn’t take a very big leak anywhere in the system to set the code and that’s if it’s a leak and not an electrical or mechanical fault.

Posted on Apr 11, 2009

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SOURCE: 2004 Toyota Sienna code P0430, Catalyst system

7 out of 10 times that means that one of the cat's have gone bad. Most of the time it happens when your mileage is around 100,000 miles. The only thing is to do is to change the bad cat.

Posted on Aug 30, 2009

  • 14 Answers

SOURCE: 2004 Dodge Neon SXT, added new battery need code to reset car

if you are the original owner, look in your paperwork. if you cant get to the original owner or they dont have the info, you can go to your dealer, and they can reset it for you. and charge you

or you can just start entering codes till it works, which will take you weeks or more.

good luck

Posted on Mar 22, 2010

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SOURCE: Error code: Code of P0420 catalyst efficiency

I assume your Vehicle is an Audi/ VW as this is a VW fault code. The o2 sensors measure the oxygen in the exhaust gases and compare it to the out side air, there by working out how efficiently the the fuel is been burnt. The engine control unit will use this and other information to adjust the fuel quantity being injected. The catalytic converter breaks down certain gases in the exhaust fumes to comply with emission regulations. Some vehicles have an upper o2 sensor [before the cat] and a lower [after the cat]. The readings of the o2 sensors is compared and should be within a certain range. If not a fault will be stored in the memory. The Catalytic converter itself may not be working correctly due to contamination or the baffle may be loose[ usually indicated by a rattle in the exhaust]. One or both o2 sensors could be contaminated with carbon and not giving accurate readings. Also check other silencers for blockages.

Posted on Jun 13, 2010

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Diagnostic Test Codes (DTCs) P0420 and P0430 ar "Catalyst Efficiency" codes. These simply mean that the catalytic converters in your vehicle are not performing the way they should be. To fix these codes, you will most likely have to replace the converters. However, these codes do NOT indicate why your engine wil not start. There are many things that can cause an engine to not start. Many of which may or may not set fault codes. You need to determine if the engine is getting fuel and ignition first then go from there.

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Basically this means that the oxygen sensor downstream of the catalytic converter on bank 1 is detecting that the catalyst is not working as efficiently as it should be. (Too much free oxygen in the exhaust downsream of the converter)

This can be caused by leaks in the exhaust system between the upstream O2 sensor and the downstream O2 sensor, but is usually caused by a converter that is chemically inactive or contaminated.

You didn't mention the year or mileage on your vehicle, but it should be noted that many manufacturers cover the catalyst under warranty for extended periods of time/mileage. If you live in the US, the manufacturer MUST warranty the catalyst for a MINIMUM of 8 years/80,000 miles per EPA mandates.

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Hi i have dodge neon 2004 the problem is apear check engie on and receive code p003 . tugging the car at any speed, i already replace spark plug but after 2 week start whit the same problem,

P0300 Random/Multiple Cylinder Misfire Detected this is the code your refering to what it means is it means your haveing a misfire in your fireing system it dosent mean that it has to be a plug could be a plug wire or a coil pack on the plug is causeing this or a faulty fuel injector replace your plug wires if it goes off if not test your injectors its in one of theses good luck

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I;ve a problem with a code defenition. p2096

This code means "Post catalyst fuel trim is to lean", what does this mean? it means that the signal coming from the sensor after the catalytic converter is always showing a lean fuel air ratio, that is what "trim means" most likely the sensor is defective, I recommend you replace the sensor after the main catalytic converter, this is the sensor that looks like an O2 sensor and is commonly called the post catalytic converter efficiency monitor, its job is to monitor the output gases of the catalytic converter and verify that the catalytic converter is doing its job of cleaning the exhaust stream. Just to make sure u have all the reasons this code is set here are all the poss reasons for the copmputer to set this code, the sensor is the most common one.

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I am getting a trouble code thats reading P0137 on my reader for a 2004 Liberty chrysler, any idea as to what the problem is

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The PO420 means that the Catalyst System has an Issue'

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"Catalyst system below Threshold (bank 1)"

As mentioned above, the code's description is Catalyst System Efficiency Below Threshold (Bank 1). OK, now tell me that again in plain English please.... let's break it down: the catalyst system being referred to is your three-way catalytic converter; so the catalytic converter is not working properly (i.e. it's not efficient). Bank 1 refers to the side of the engine which contains cylinder #1. On inline engines such as 4 & 5 cylinder engines, there is only one bank. So, to really simply things let's just say that the efficiency of the catalytic converter and/or exhaust pipe and/or O2 sensor is not so great.

There are a number of things that could be causing this p0420 catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear O2 (oxygen) sensor is no longer working properly. Other things could include exhaust leaks, damaged exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter, etc.

You can search for the Information on the web. Just type in the actual error above into you fav search engine!

Hope that helps...

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