Check engine light is on for the catalytic converter , I fixed one about a year ago. Is there a part needed, Frontback? Which part

With my car , I got my catalytic converter fixed about a year ago. But now the check engine light is on for it again now. The guy at autozone said there are different parts for it. Front/back ? So I am assuming I need to change a different one ? Also he showed me pictures of a smaller one and a longer one. How would I know which one to buy to get it fixed ? And where would I go to get it fixed ? I feel he was trying to get me to buy a more expensive one but looking online I see some for $140 and below. So I am super lost here please help asap.

My car has 185000 miles.
My car has an a

Experienced mechanics share their insights in answering this question :
Since your vehicle has a V shaped engine, it will likely have two catalytic converters. Since the engine is mounted transversly in the vehicle (because it is front wheel drive) there will be one converter on the front and one on the rear. If you had one replaced, it is likely the issue is coming from the opposite converter. I would recommend having your exhaust system inspected by a qualified professional who has experience in exhaust system diagnosis and repair.

How to Identify and Fix Common car Problems ?

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Malfunctioning Sensor: There are several sensors in your vehicle that help monitor the performance of the engine and emissions system. If one of these sensors is malfunctioning or was damaged during the catalytic converter replacement, it could trigger the service engine soon light.
The catalytic converter converts harmful byproducts of internal combustion to less-harmful compounds. If there`s an exhaust leak letting gasses out of the system before it reaches the converter, if the converter becomes damaged or if it`s missing altogether, the check engine light will activate in your dashboard.
In most cases, successfully repairing the issue that caused your light to come on will cause the check engine light to turn off automatically—but only after 10 to 20 “cycles”.
Aftermarket 02 sensors have been known to cause check engine lights when used with some aftermarket CATs. If a check engine light is on even after an acceptable aftermarket CAT has been installed, the vehicle will not pass smog.
As part of a car`s exhaust system, the catalytic converter helps to reduce air pollution. You will not harm your engine or your car in any way by driving without a catalytic converter.
The code P0420 can be caused by the catalyst, O2 sensors before and after the catalyst. If both O2 sensors and catalyst was replaced then you may have an exhaust leak at the manifold or pipes.
To start the break-in procedure, start the car after you`ve replaced the cat. Let the car idle in place without applying any gas. When the engine warms up to its operating temperature, get inside and give the car enough gas to bump the RPMs to around 2500. Hold it there for 2 minutes and then release the gas.
Not necessarily. For example, if the catalytic converter fails because of cracked welds or because the element inside broke up into tiny pieces, the oxygen sensors will be fine (usually there`s an upstream and a downstream oxygen sensor in modern vehicles).
What the catalytic converter warning light means. This light is made to warn the driver that the catalytic converter is either overheating or not operating as intended. The inside of the catalytic converter consists of a honeycomb design that increases the surface area in contact with the air.
To make sure the check engine light does not reappear, it`s recommended that you drive your car 30 to 100 miles. This enables the vehicle`s “Drive Cycle” to reset, as the various sensors need time to recalibrate.
To start the break-in procedure, start the car after you`ve replaced the cat. Let the car idle in place without applying any gas. When the engine warms up to its operating temperature, get inside and give the car enough gas to bump the RPMs to around 2500. Hold it there for 2 minutes and then release the gas.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Check engine light is on for the catalytic converter , I fixed one about a year ago. Is there a part needed, Frontback? Which part
ANSWER : Since your vehicle has a V shaped engine, it will likely have two catalytic converters. Since the engine is mounted transversly in the vehicle (because it is front wheel drive) there will be one converter on the front and one on the rear. If you had one replaced, it is likely the issue is coming from the opposite converter. I would recommend having your exhaust system inspected by a qualified professional who has experience in exhaust system diagnosis and repair.

p0011 code,check engine light one, changed bank 1 vvt solenoid and check engine light still on?
ANSWER : The P0011 code is typically caused by oil issues with the car. I would particularly make sure the engine oil level is not low. The VVT solenoid relies on proper oil levels to do their job. If they don’t have enough oil, they won’t work. You can have a mobile technician from YourMechanic visit your home or office to inspect the Check Engine Light for you. If you follow through with a repair with us you will be reimbursed for the cost of inspection.

Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.

Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.

To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.

Traction light/reduced engine power and check engine light coming on
ANSWER : Hello. From what you describe, it would appear that your vehicle may be experiencing some sort of intermittent wiring or sensor issue. If the problem occurred again after driving over a bump, then it may be possible that a damaged or loose wire is shorting or having contact issues. A common issue that can cause stalling is a faulty crank position sensor or wiring. I would carefully examine the engine for any loose or damaged wires. If the Check Engine Light comes back on, I would recommend having the trouble codes scanned before resetting the computer.

2006 Ford Mustang has check engine light on
ANSWER : There are countless potential causes for your illuminated check engine light. The mechanic manually turned off the light, but it came back on because the problem has not been fixed. The first place to start is retrieval of the stored diagnostic trouble codes (DTCs). These codes serve as a starting point for any further diagnostics a mechanic may perform. Codes will be stored anytime the check engine light is on. Since the first mechanic was unable to fix your concern, I recommend giving the professionals at YourMechanic a call. We offer expert check engine light diagnosis and repair.

While driving on freeway truck goes into a limp mode, and the check engine light, abs light, parking break light, service brake
ANSWER : It is possible that you could be having an issue with your powertrain control module. This is somewhat of a common problem on many GM vehicles. I would recommend having your vehicle inspected by the dealership to determine if the powertrain control module is functioning properly. If not, a reflash of the powertrain control module may resolve the issue but often times it must be replaced.

Check Engine Light is on, trouble code P0011&12. I changed the oil and filter. I need to turn off the engine light to see if that problem is solved.
ANSWER : Hello. If the oil level was low or if the wrong oil war previously used then that can cause these codes to come up. Most of the time though, on this engine, it is caused by a failure in the timing chain. The timing chain is the most common failure on this engine and when it is stretched enough the cam timing will be off enough to cause this. If you want to have this camshaft timing looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose why the check engine light is still on and address any issues that are found.

Car goes into limp mode when the check engine light and VSA light comes on
ANSWER : The lights that you have on and the vehicle going into fail safe mode is an indication you have a major system failure that will require computer to be tested for codes first. There are many possible codes it can be so the additional testing will be needed to isolate the cause of the problem.