An expert who has achieved level 3 by getting 1000 points
An expert that got 10 achievements.
An expert that got 5 achievements.
An expert whose answer got voted for 500 times.
Re: 1998 Chevrolet Cavalier 0420 Code
Here is something from a reference guide that we follow at my shop, hope it helps.
When diagnosing a PCM code PO420, be sure to determine the cause of the converter failure. Converters are not likely to fail without an external cause. Typical causes are: fuel pressure regulator leak, engine misfire, dirty fuel injectors, coolant consumption, etc. Also, be aware that some converters on the market will cause this code or codes due to a lack of oxygen storage capacity. A component that must be in these converters, Cerium, is required to store, then slowly release oxygen.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
codes p 0014, 0340, 0341, 0345, 0346 all refer to the cam shaft position sensor==causes include-- advance mechanism faulty - CMP sensor --insecure cam rotor --wiring short to ground --air gap--ECM
codes p 0420, 0431 refer to the cat converter=== causes --cat converter failed ---wiring --- HO2S ( heated oxygen sensor)
code p 171 is a faulty HO2S sensor and
p 174 refers to system too lean bank 2===causes --intake /exhaust leak---fuel pressure /pump---injectorr/s AIR system---hose connection/s
you will need a cat converter to make the system work properly
code p 0420 refers to cat converter system bank 1-efficiency below threshold===causes ---cat converter, ---wiring---HO2S 2 sensor
have you been replacing the correct sensor as they are different in operation
code p0420-430 refers to both cat converters (bank 1 and bank 2)--efficiency below threshold== cause cat converter- wiring --- Ho2s. As cat converters are subject to cracking and failing and thereby not doing the job I would suggest having them checked and replaced if necessary. A local exhaust shop should be able to do the job . If they are cracked/broken there will be a rattling sound when the exterior is hit
code p0171 refers to system to lean bank 1==causes intake /exhaust leak--AIR system--MAP/MAF sensor--fuel pressure/pump--injectors--HO2s Have a fuel pressure test done on the fuel manifold to check for blocked filter/faulty pump/fuel pressure regulator faults code p0174 refers to system to lean bank 2 --same causes including hose connection/s code p0420 refers to catalytic converter system -bank 1 efficiency below threshold==causes catalytic converter--wiring--HO23. Check the cat converter is not cracked inside and the oxygen sensor is working.
Air leaks at the exhaust manifold or in the exhaust pipesBase engine problems (i.e., high engine oil or coolant usage)Catalytic converter is damaged, contaminated or has failedContinuous engine misfire conditions, or weak or low coil outputFront HO2S or rear HO2S is contaminated with fuel or moistureRear HO2S is loose in the mounting hole (check it for a leak)Front HO2S older (aged) than the rear HO2S (HO2S-12 is lazy)
code P1133 is for a problem with 02 sensor bank one sensor one. this is the left 02 sensor in front of the cat. converter. code P1153 is for a problem with 02 sensor bank 2 sensor 1, which is located on the right side of engine in front of the cat. converter
well a P0172 is a rich condition. meaning too much fuel entering the exhaust. a bad wire, plug, stuck open fuel injector, and or a bad fuel pressure regulator could be the problems. Just have to start testing each one.