Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

2 months ago my car wouldn't start. My mechanic put in a new ignition switch, but when I left the shop I noticed my radio suddenly wasn't working. After that I started having problems with the car losing power/speed, but there were no other symptoms, no error codes, no check engine. No mechanic can figure out why or whats wrong with the car. Recently I noticed the radio DOES work in accessory mode so I think the ignition switch may be faulty. And today my muffler just started making a rumbling noise so I'm thinking maybe it's the catalytic converter or muffler. My question is –
Experienced mechanics share their insights in answering this question :
Hi There,
The catalytic converter is entirely unrelated to the ignition switch and neither of these should impact the other. The catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When the catalytic converter is clogged, this causes these gases to be backed up into the exhaust system not allowing the engine to breathe properly. When this happens, the engine is forced to work much harder to expel these gases. This often results in the engine bogging down, hesitating, shaking and causing very poor fuel economy. This should also cause a check engine light to come on as the O2 sensors should be reading the incorrect amounts of oxygen in the exhaust gases if this is your problem. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your catalytic converter.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Hard Starts and Stalling

If an ignition coil is malfunctioning and not delivering the required voltage to the spark plugs, you will find it hard to start the engine. If your vehicle stalls when you stop and even shut off completely, it could be a bad ignition coil sending irregular sparks to the spark plugs.

Very few ignition switches fail catastrophically. Most begin to fail intermittently and are usually sensitive to temperature and humidity.
An ignition issue can be caused by a faulty or failing ignition coil, spark plug, or spark plug wire set. These critical components of your ignition system keep your engine running smoothly.
The first thing to inspect is your plug wires. Any signs of damage or decay are clear indicators that they`re your issue. To verify, you`ll want to check the resistance of the wires.
Make Sure the Gas is On

Therefore, the first step in diagnosing ignition failure is to make sure the gas is turned on. If your furnace starts after the fuel source is turned on, you`ve solved your problem.

A dead battery is one of the most common reasons why your car won`t start. Check the battery terminals for corrosion and clean them using a wire brush or battery cleaning solution. If the battery is old or damaged, it may need to be replaced entirely.
Typical issues that you will encounter when troubleshooting the ignition system include a dead battery, faulty spark plugs, ignition coils, or distributor. Ignition troubleshooting involves a series of tests and inspections to determine the root cause of the issue and take corrective actions to fix the problem.
An Issue With The Ignition Control Module

If the ignition control module has failed altogether, it`ll create a weak spark, and the car won`t start. Check to see if the switch and terminals are free from rust and replace any damaged or broken spark plugs wires as necessary.

What kills ignition coils is location; being mounted in one of the hottest, most vibration prone and dirtiest parts of the engine. Modern ignition coils are typically located between two camshafts on the valve cover and exposed to dirt and oil.
A typical problem with the ignition switch is when your car fails to start. This sign forces you to keep making attempts to turn the engine, draining and, therefore, killing your battery.
When a solenoid is first energized, its coil receives a pulse of high inrush current that decreases as the plunger closes. If the plunger does not close, the high inrush current continues, which can cause the coil to overheat and burn out. This is the most common cause of solenoid failure and spotting it is easy.
When you have a bad starter solenoid, the starter motor won`t work. This means the engine won`t start when you turn on the starter switch or press the start button. However, if your vehicle has an automatic transmission, the engine could sometimes not crank because of the neutral safety switch.
To check the voltage reaching the starter, connect the voltmeter to the starter feed terminal and earth it on the starter casing. Test the voltage reaching the starter. For a negative-earth system on a car with a pre-engaged starter, connect the positive lead of the voltmeter to the feed terminal on the solenoid.
Bad Sensors

One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft. The computer uses the information from this sensor to know when to fire the spark plugs. If the sensor isn`t working, the spark plugs won`t fire, keeping the engine from starting.

Most vehicles will require a new key when replacing an ignition switch, as the old key has worn down and is incompatible with the new set. However, some cars may be able to use an existing key, depending on the condition and make of the key.
Your engine may not start if an ignition coil isn`t firing up a spark plug. It could be a faulty coil, a poor connection to the ignition coil, or a control module that`s causing the problem.
Your spark plugs can damage your vehicle`s ignition coil if they are dirty or worn. Check your owner`s manual to see when you should have your spark plugs replaced and then don`t put the service off. Your engine performance and fuel economy will also be affected by worn spark plugs.
Locate the positive or power wire attached to the engine coil. Check for power using a test light. If this wire has no power, then your ignition coil is not receiving current. You should check the wiring from your ignition switch to the coil for breaks in the wire and repair them.
If the ignition coil does not have spark, it`s time to check its wires. Use a test light to check the continuity on the signal wire and power wire on the ignition coil. If both wires are functional but the coil fails to produce spark, the ignition coil or the ignition control module is bad.
In bypass starting, you touch a wrench or a screwdriver to the terminals of the starter motor, to the solenoid of a tractor, or to other equipment. This bypasses all tractor-neutral starting switches. Sparks fly and electricity snaps as the circuit is completed, the starter engages and the engine starts.
Starter motors should make noise when you turn your ignition key fully to activate your car. If you turn the key and do not hear anything, there`s a chance that there`s something wrong with the vehicle`s ignition switch.
Solenoid coil failure can be caused by a number of factors. Applying an incorrect voltage to the coil will cause it to fail and may cause the coil to burn out. Electrical surges or spikes may also damage the coil. Burnt out coils cannot be repaired and will need to be replaced.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?
ANSWER : Hi There,
The catalytic converter is entirely unrelated to the ignition switch and neither of these should impact the other. The catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When the catalytic converter is clogged, this causes these gases to be backed up into the exhaust system not allowing the engine to breathe properly. When this happens, the engine is forced to work much harder to expel these gases. This often results in the engine bogging down, hesitating, shaking and causing very poor fuel economy. This should also cause a check engine light to come on as the O2 sensors should be reading the incorrect amounts of oxygen in the exhaust gases if this is your problem. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your catalytic converter.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

Car will not crank after putting in a new starter. Forced starter to start up and engine starts but stalls out. Will the security continue to cut off fuel while force starting?
ANSWER : Hi there. Forcing the starter to engage to make the engine run without the ignition engaging the starter will continue to keep the security on. This is a safety feature that keeps people from stealing your vehicle. I recommend replacing the ignition switch and checking the wires to make sure that they are all tight and clean. If you need further assistance with diagnosing your ignition problem, then seek out a professional, such as one from Your Mechanic, to help you.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

My car cranks but will not start. I try to do fix the car myself. I put new battery, new alternator, and new ignition coils.
ANSWER : Hi there. Check the spark plugs and see if they are worn or burned. If the plugs are good and they have a good spark, then the engine compression could be low causing a no start situation. If the spark plugs are not emitting a spark, then the crankshaft position sensor could have failed or disconnected. Check the crankshaft position sensor wiring harness and make sure that its plugged in. Check the sensor and make sure that its not broken or damaged. If you need further assistance with your engine not starting, then seek out a professional, such as one from Your Mechanic, to help you.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

I put a new ignition switch in my 2004 Chrysler Pacifica but it still wont start, how do I program the ignition switch?
ANSWER : Hello. If your vehicle is not cranking, then I would first verify that the starter and electrical system are functioning correctly. Aside from a bad ignition switch, a few common causes for a no crank condition are a faulty starter, starter solenoid, starter relay, or bad wiring. If you replaced the switch, and wish to program the new keys the procedure is as follows:

Note: You must have two valid keys to add a new key to the system.

Insert the first valid key into the ignition switch. Turn the ignition switch to the
ON/RUN position for at least three seconds, but no longer than 15 seconds.
Then, Turn the ignition switch to the LOCK position and remove the first key.
Insert the second valid key into the ignition switch. Turn the ignition switch to the ON/RUN position within 15 seconds. After 10 seconds, a chime will sound. In addition, the Vehicle Security Light will begin to flash. Turn the ignition switch to the LOCK position and remove the second key.
Insert the new key into the ignition switch. Turn the ignition switch to the ON/RUN position within 60 seconds. After 10 seconds, a single chime will sound. In addition, the Vehicle Security Light will stop flashing. To indicate that programming is complete, the Vehicle Security Light will turn on again for seconds and then turn off.

The new key should now be programmed. The Remote Keyless Entry transmitter will also be programmed during this procedure. Repeat this procedure to program up to eight keys. If you are still having problems with this after you’ve replaced the key, a certified technician from YourMechanic can come to your car’s location to inspect the cranking issue.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

I put the wrong key in my car and a few weeks later my car just shut down and it will not start I believe it’s the computer but…
ANSWER : Hi there. What had happened is the wrong key set the security to the vehicle. This is to prevent the vehicle from starting with the wrong keys. Try removing the battery cables (+) and (-) for 13 minutes. During that time, put the original key in the ignition and turn it on. Activate everything in the car even though there is no power. Then remove the key and hook up the battery cables. The computer should have reset and reset the security. If the security is still being tripped, then I recommend seeking out a professional, such as one from Your Mechanic, to help you

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

My car won’t start I just got a new starter , when I try to start my car it make a click sound nothing else.
ANSWER : Hi there. It sounds like a weak battery, however there are other possibilities that can create the same symptom. Has the battery been tested? Have it tested with a digital volt/ohm tester that provides current voltage, cold cranking amps, and state of health; replace as necessary. Any corrosion on the terminals? Do the terminals fit properly? Corroded and loose terminals prevent proper voltage and amperage from reaching the starter and will need to be repaired. Has a voltage drop test been performed on the cable to the starter to check for excessive resistance? Any corrosion that makes its way into the cable can create resistance and lower the available voltage and amperage to the starter; this will need to be replaced if this is the case. If all checks ok, then the new starter could be faulty and need to be replaced. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a car does not start inspection.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

I put a new ignition switch in my 2004 chrystlwr pacifica but it still wont start, how do i program rhe ignition switch?
ANSWER : Hello.

If your vehicle is not cranking, but the lights and accessories come on then it may be possible that the issue is rooted elsewhere. I would verify that the starting and electrical system are in good order. A no crank condition can be caused by a faulty battery, starter, starter solenoid, relay, or any of the wiring associated with these components. I would start with checking the battery and starter, and go from there. If you wish to program your new switch and key, the procedure is as follows:

Note: You must have two valid keys to add a new key to the system.

Insert the first valid key into the ignition switch. Turn the ignition switch to the ON/RUN position for at least three seconds, but no longer than 15 seconds. Then, Turn the ignition switch to the LOCK position and remove the first key.
Insert the second valid key into the ignition switch. Turn the ignition switch to the ON/RUN position within 15 seconds. After 10 seconds, a chime will sound. In addition, the vehicle security light will begin to flash. Turn the ignition switch to the lock position and remove the second key.
Insert the new key into the ignition switch. Turn the ignition switch to the ON/RUN position. Within 60 seconds. After 10 seconds, a single chime will sound. In addition, the Vehicle Security Light will stop flashing. To indicate that programming is complete, the Vehicle Security Light will turn on again for seconds and then turn off.

The new key is now programmed. The Remote Keyless Entry transmitter will also be programmed during this procedure.

Repeat this procedure to program up to eight keys.

If you need some assistance with this, consider YourMechanic, as one of our certified technicians can diagnose the starting issue firsthand and perform this procedure as necessary.

Read Full Q/A … : Got a new ignition switch, car starts now but believe it’s faulty. Can a bad ignition switch damage the catalytic converter?

Eric smoalih

I am a certified master technician with the National Institute for Automotive Service Excellence (ASE), and I have been working as an auto mechanic for over 15 years. I am passionate about my work, and I take great pride in helping people keep their cars running smoothly.