$250 oxygen sensor parts only 2002 Jeep GC too much? needed?

Hi there:



The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.


You will likely not notice any drivability problems, although there may be symptoms.


A code P0420 may mean that one or more of the following has happened:

Leaded fuel was used where unleaded was called for

An oxygen sensor is not reading (functioning) properly
The engine coolant temperature sensor is not working properly
Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe
******** spark timing
The oxygen sensors in front and behind the converter are reporting too similar of readings




Some suggested steps for troubleshooting a P0420 error code include:
Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.

Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
Inspect the downstream heated oxygen sensor (HO2), replace if necessary
Replace the catalytic converter


One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.


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Hi there:

The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.

A code P0420 may mean that one or more of the following has happened:
Leaded fuel was used where unleaded was called for an oxygen sensor is not reading (functioning) properly
The engine coolant temperature sensor is not working properly
Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe
******** spark timing
The oxygen sensors in front and behind the converter are reporting too similar of readings

Some suggested steps for troubleshooting a P0420 error code include:
Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.
Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
Inspect the downstream heated oxygen sensor (HO2), replace if necessary
Replace the catalytic converter
One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.

Hope helps.

this obd2 trouble code table can help you understand the meaning of code.
and for the p0420, you can try :

Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.

Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).

Inspect the downstream heated oxygen sensor (HO2), replace if necessary

Replace the catalytic converter

One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.

for p0430, try:

.

First, inspect for exhaust leaks.

Next step is to measure the voltage at the oxygen sensor on Bank 2. In fact, it would be a good idea to test each oxygen o2 sensor while you're at it.

One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.

Replace the 02 sensor bank 1. Although there was a service bulletin for your year car. Ask your dealer about it. Also might be covered under warranty

P0430 - Catalyst System Efficiency Below Threshold (Bank 2)

Basically this means that the oxygen sensor downstream of the catalytic converter on bank 2 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.

Symptoms: You will likely not notice any drivability problems, although there may be symptoms such as a rough/hard idle when cold.

Causes: A code P0430 may mean that one or more of the following has happened:
* The catalytic converter is no longer functioning properly
* An oxygen sensor is not reading (functioning) properly
* There is an exhaust leak

Possible Solutions:
* First, inspect for exhaust leaks.
* Next step is to measure the voltage at the oxygen sensor on Bank 2. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.

One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.



P1572 - ASCD Brake Switch Circuit Malfunction
For check ASCD BRAKE SWITCH POWER SUPPLY
- Turn ignition switch OFFDisconnect ASCD brake switch (2) harness connector Stoplamp switch (1) Turn ignition switch ON
- Check voltage between ASCD brake switch terminal and ground under the following conditions with CONSULT-II or testerCONDITION VOLTAGE Battery voltage Approx. 0V

More than likely the brake pedal cancellation switch is bad.

Keep us updated.

The definition of code P0420 Is Catalyst Efficiency. You may have an oxygen sensor problem or a catalytic converter problem. Your vehicle has 2 oxygen sensors. Check your oxygen sensors.If they are then you may need a catalytic converter. Depending on your mileage it may be covered under a Dodge emissions warranty. Have it checked by a certified garage first and in the meantime contact your local Dodge dealer and find out the emissions warranty most are 8 yr or 80,000 miles.

Well your exhaust system may still be under the 8-80 warranty, so I would check with the dealer. My 01 had 4 sensors, an upper and lower on each side. Yours has at least 2 so replacing one did not update the other, and your converter(s) may have failed. So I would start by checking your VIN with a dealer to see if you are still under the 8 year/80,000 mile warranty on the exhaust system. If not I would have them do a diagnostic on it to see what is bad.

Replace the fan relay switch. The dealer will charge you 400 to pull the bumper off, or you can buy the part for 45 and cut the hole in the plastic near the passenger headlight assembly and replace it yourself. There are instructions for this procedure on the web somewhere. I have had this problem more than once with my 02 GC V6.

OK Thad code PO136 is your oxygen sensor the one before the catalytic converter and yes if your you bought your car brand new
from the dealer ship yes you are covered by the factory warranty
but if you got it from a used car dealer then you are not.

If you are not covered the good news is than that is not so hard to change.
all you need is a jack a oxygen sensor tool ( you can get it as a loaner on Auto Zone no charge ) and a new oxygen sensor.

If you don't know how a catalytic converter looks like click this link
good luck.
http://cgi.ebay.com/ebaymotors/2002-TOYOTA-TACOMA-MAGNAFLOW-CATALYTIC-CONVERTER-23759_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem3a4ae004b7QQitemZ250364298423QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ebayphotohosting

Unless you had warranty transferred, your probably out of luck, but to confirm, call a Chrysler/Jeep dealer, ask for service dept. and service writer or manager can tell you by your VIN#, so have it ready, as well as your current mileage.