Muffler part In 2005 I got my muffler and catalytic converter and muffler replaced, with a lifetime warranty on the parts. I just got the muffler replaced again on the warranty last year. Now apparently my resonator assembly is shot - apparently it is the middle component between the catalytic converter and muffler - wouldn't they have replaced the whole thing in 2005? It's a 99 Firefly, but it didn't show the right year option.

Starting from the front, coming off the exhaust manifold should have, 1. Exhaust pipe, 2. Catalytic converter, 3. Exhaust pipe, 4. Resonator, 5. Tail pipe. Also, there should be an Oxygen sensor somewhere around the catalytic converter.

P0420 OBD-II Trouble Code Technical Description Catalyst System Efficiency Below Threshold (Bank 1) What does that mean? This diagnostic trouble code (DTC) is a generic powertrain code. It is considered generic because it applies to all makes and models of vehicles (1996-newer), although specific repair steps may be slightly different depending on the model. So this engine code article applies to Nissan, Toyota, Ford, GM, etc. The catalytic converter is a part of the exhaust system that looks kind of like a muffler, although it's job is very different from that of a muffler. A catalytic converter's job is to reduce emmissions from the exhaust. 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). Catalytic converters are not normally a "wear" type item, that is they are not deisgned to wear out and need replacement. If they have failed, it is likely due to something else that caused it to fail. Symptoms The main symptom to the driver is the illumination of the MIL (malfunction indicator lamp). You will likely not notice any drivability problems, although there may be symptoms. For example, if the substance inside the catalytic converter is broken or failed, it may be restricting the exhaust which will result in a feeling of reduced power output from the vehicle. Causes A code P0420 may mean that one or more of the following has happened: Leaded fuel was used where unleaded was called for A damaged or failed oxygen sensor (HO2S) Downstream oxygen sensor (HO2S) wiring damaged or connected improperly The engine coolant temperature sensor is not working properly Damaged or leaking exhaust manifold / catalytic converter / muffler / exhaust pipe Retarded spark timing The oxygen sensors in front and behind the converter are reporting too similar of readings Leaking fuel injector or high fuel pressure Cylinder misfire Oil contamination Possible Solutions 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 (HO2S), replace if necessary Replace the catalytic converter Overall probably the biggest mistake vehicles owners make when they have a P0420 code is to simply replace an oxygen sensor (H02S). It is important to do proper diagnosis so you're not wasting money replacing parts unnecessarily. We strongly recommend that if you need to replace the catalytic converter that you replace it with an OEM unit. Second choice would be a high-quality replacement part. There are many stories in our forums where folks replaced the cat with a cheaper aftermarket one only to have the code return shortly thereafter. 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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I suggest you get one of those manuals people get nowadays to do it yourself.. My nephew use it to fix my car and it's totally repaired now. Here's the website he bought it from.
www.reliable-store.com

I suggest you get one of those manuals people get nowadays to do it yourself.. My nephew use it to repair my car and it's totally repaired now. Here's the website he bought it from.
www.reliable-store.com

one on each header pipe and one in the pipe further back..dont go to a dealer..go to a muffler shop.. they are much cheaper..

Hi,
CO2 or just O2 sensor? O2 sensor may be going bad due to blocked/plugged catalytic converter. This can be replaced @ muffler shop...use a 'universal' type catalytic converter to save some money - you don't have to use a manufacture unless your state requires it.

Td

Catalytic Converter Removal & Installation 2.2L Engine To Remove:
Catalytic converter 2.2L engine

1. Raise and safely support the vehicle.
2. Disconnect the heated oxygen sensor (HO2S) electrical connector.
3. Remove the exhaust manifold pipe flange mounting nuts from the catalytic converter.
4. Remove the catalytic converter flange mounting nuts from the muffler.
5. Remove the catalytic converter from the muffler.
6. Remove the catalytic converter from the rear hanger bracket insulator.
7. Remove the catalytic converter.
8. Remove the (HO2S) from the catalytic converter.

To Install:

1. Install the (HO2S) to the catalytic converter.
2. Install a new gasket and the catalytic converter to the muffler.
3. Install catalytic converter to the catalytic converter hanger.
4. Install the catalytic converter flange mounting nuts to the muffler flange.
   • Tighten to 26 ft lbs (35 Nm).
5. Install the catalytic converter flange mounting nuts to the exhaust manifold pipe flange.
   • Tighten to 26 ft lbs (35 Nm).
6. Connect the heated oxygen sensor (HO2S) electrical connector.
7. Lower the vehicle.

------ Catalytic Converter Removal & Installation 4.3L Engine To Remove:

1. Raise and safely support the vehicle.
2. Raise and support the transmission.
3. Remove the transmission support
4. Disconnect the left and right pre-converter heated oxygen sensor (HO2S) electrical connector.
5. Disconnect the post-converter (HO2S) connector. Muffler flange and gasket
   
   
6. Remove the catalytic converter flange mounting nuts from the muffler.
7. Remove the catalytic converter from the muffler.
8. Remove the exhaust manifold flange mounting nuts from the catalytic converter. Catalytic converter 4.3L engine
   
   
9. Remove the catalytic converter from the support bracket insulator.
10. Remove the catalytic converter and gaskets.
11. Remove the heated oxygen sensor.

To Install:

1. Install the heated oxygen sensors as needed.
2. Install a new gasket and the Install the catalytic converter to the support bracket insulator.
3. Install the catalytic converter to the exhaust manifold flange. Install the mounting nuts.
   • Tighten to 39 ft lbs (53 Nm).
4. Using a new flange gasket, install the catalytic converter to the muffler. Install the mounting nuts.
   • Tighten to 30 ft lbs (40 Nm).
5. Connect the left and right pre-converter heated oxygen sensor (HO2S) electrical connectors.
6. Connect the post-converter (HO2S) electrical connector.
7. Install the transmission support.
8. Lower the transmission.
9. Lower the vehicle.

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It looks like you can cut them and replace them with new bolts and nuts.

Advance auto and auto zone sell just the flex pipe. You will need to have someone cut the old one out and weld the new one in. costs about $20 for part vs $300 for pipew/catalitic converter attached.

if the converter is rattlin then it needs to be replaced because the element inside is broken. if the jeep still does not run try removing the catalytic converter to see if the restriction is too much. should start if the converter is restricted. if it doesnt maybe its whatever caused the converter to go bad in the first place

HI, this guide will help you with this replacement.

Step1 Lift your jeep. Unfortunately, the catalytic converter sits about midway down the length of your jeep, so lifting one end or the other will not do. Ramps are your best bet to get you within reach of the parts when working from home. Luckily, this is usually the hardest part of this repair. Step2 Be patient with the bolts, as they are often hard to remove due to size and awkward placement. You may have to drill or saw bolts to remove them. With this in mind, you should pick up new bolts, nuts and seals for your replacement project. Step3 Buy a catalytic converter specific to your jeep to avoid extra work. A generic part must be welded into the jeep, while a vehicle-specific model comes pre-welded to the proper pipes for easy bolt-on installation. Step4 Remove the 02 sensor (with an O2 wrench) before unbolting the catalytic converter. Then, you should remove the pipe connecting the sensor to the converter. Depending on your exhaust system, you may have to remove more pipes before you unbolt the converter from the muffler. Step5 Replace the old catalytic converter with a new one. This should be the easy part, as you simply bolt the new part in place. Step6 Reattach the exhaust pipes and 02 sensor, and the basic job is done. Make sure you replace any cracked or rusty pipes while you have the exhaust system apart.

• Catalytic converters often fall under a separate emissions warranty that lasts at least 7 years and 160,000 miles. Even if your car is out of its regular warranty, but it is a newer model, ask your dealer to replace the part for you free of charge.
• Rent the O2 wrench or socket if you do not own one. Most auto parts stores carry this tool for rentals.
• In many states, older (vintage) cars do not need a catalytic converter, so you can gut it or remove it completely. No damage will result from running a car without a converter.
• Due to emissions standards, it is illegal to buy or install used converters.

Please rate and god bless:)