Backfires and doesn’t do anything
My car runs at idle, but has a very bad backfire, and doesn't do anything when the gas pedal is pushed.
Experienced mechanics share their insights in answering this question :
There are a number of potential causes for your problem. A couple things come to mind, however. The first is a collapsed catalytic converter. A collapsed converter could both cause engine backfiring, as well minimal acceleration. Misadjusted timing could also cause this problem. Your vehicle has a distributor, but the timing is fixed and controlled by the power train control module (PCM). A trained mechanic will be able inspect your vehicle first hand and diagnose your gas pedal problem and idling issue.
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An engine backfire occurs whenever the air-fuel mixture in your car combusts somewhere outside the engine`s cylinders. This can cause damage to your car`s exhaust or intake if left unchecked — and it also means that your car`s engine isn`t making as much power as it should, and is wasting lots of fuel.
This can be caused by a faulty mass airflow sensor or a clogged engine air filter “choking” the engine and not allowing enough oxygen to flow into it. Or, it could be caused by leaking fuel injectors forcing too much fuel into the engine.
If too much fuel is added to the engine, it may not all burn up before the exhaust valves open — letting unburned gasoline into the red-hot exhaust headers, where it can combust and lead to a backfire. Too much fuel could be getting into your engine due to damaged and leaking fuel injectors or bad engine sensors.
Too much fuel and not enough air causes a ratio that`s too rich. This can cause some of the mixture to combust in the exhaust instead of inside the combustion chamber. The mass airflow sensor, fuel injectors, and engine air filter are all components that your mechanic will check if your fuel ratio is too rich.
If the engine doesn`t have enough air, the air-to-fuel mixture ratio is off, and some fuel might be left after the spark. This fuel then makes its way through the system and could cause a backfire.
Another possible cause of your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.
Backfiring. When your vehicle starts to backfire, a bad ignition coil could be the culprit. A vehicle makes a loud bang sound when unused fuel in the combustion cylinders explodes, causing black smoke to emerge from the exhaust pipe and the strong smell of gas.
There`s a variety of factors that can cause your car to backfire, but the most common ones are having a poor air to fuel ratio, a misfiring spark plug, or good old-fashioned bad timing.
Explanation. Common causes of backfire are running rich (too much fuel going into cylinders) or faulty ignition, possibly a fouled (dirty) spark plug, coil, or plug wire. Pop-backs are usually caused by problems with timing.
Misfiring on one or more cylinders can cause a rough running or backfiring condition. Misfires can be caused by lack of spark or lack of fuel to any cylinder.
Backfiring in internal combustion engines occurs outside of the combustion chamber, and is typically the result of an improper air to fuel ratio. An overly lean air-fuel mixture (i.e. an overabundance of air) can lead to a failure to ignite in the combustion chamber, also called a “misfire”.
Common signs include irregular or unusually high idle speed, the Check Engine Light coming on, and stalling while idling.
Cracked distributor cap
Cars that don`t have ignition coils on their spark plugs have a distributor cap and a wire set that disperse the electrical pulse to the spark plugs. If the cap is cracked, it allows moisture to creep in, which causes the electrical spark to jump to the wrong cylinder, causing a backfire.
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.
On the other end of the spectrum, a bad fuel pump, vacuum leak, or clogged fuel injectors could cause an air-fuel ratio that`s too lean; that is, it has too much air and not enough fuel. Though this is the opposite problem, it can also cause a backfire as vapor escapes into the exhaust and combusts there.
Pop and bang tuning has certainly gained a poor reputation. But social acceptance aside, is it true pops and bangs tuning can damage your engine? The short answer is yes! The excess fuel added to cause the anti-lag and pops is not at all good for the longevity of an engine.
On the other end of the spectrum, a bad fuel pump, vacuum leak, or clogged fuel injectors could cause an air-fuel ratio that`s too lean; that is, it has too much air and not enough fuel. Though this is the opposite problem, it can also cause a backfire as vapor escapes into the exhaust and combusts there.
Another possible cause of your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.
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Backfires and doesn’t do anything
ANSWER : There are a number of potential causes for your problem. A couple things come to mind, however. The first is a collapsed catalytic converter. A collapsed converter could both cause engine backfiring, as well minimal acceleration. Misadjusted timing could also cause this problem. Your vehicle has a distributor, but the timing is fixed and controlled by the power train control module (PCM). A trained mechanic will be able inspect your vehicle first hand and diagnose your gas pedal problem and idling issue.
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My car wouldn’t revv above 3 rpm and when in motion, it doesn’t exceed 2 rpm, as such, it doesn’t select gear properly. The car
ANSWER : Hi there. To be honest, this problem could be caused by multiple fuel system or ignition system components. Some common reasons that an engine won’t accelerate properly include dirty EGR valve, mass air flow sensors, or clogged fuel injectors / throttle body issues as well. Some ignition components such as damaged or worn out spark plugs or distributor cap can also cause this problem. In order to correctly diagnose this problem, it would be best to have a professional mobile mechanic come to your location and complete a engine idle is rough inspection.
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The RPM doesn’t exceed 3 on the dash board when idling, and rpm doesn’t exceed 2 when in motion. What is the cause?
ANSWER : Hi There,
It sounds like you may have a problem with your transmission causing it to go into limp mode which will not allow the car to exceed a specific RPM or speed when driving. The transmission control module will purposely do this when there is an error detected in the transmission such as a faulty speed sensor or solenoid.
It sounds like you may have a problem with your transmission causing it to go into limp mode which will not allow the car to exceed a specific RPM or speed when driving. The transmission control module will purposely do this when there is an error detected in the transmission such as a faulty speed sensor or solenoid.
A clogged or failing catalytic converter can also cause the vehicle to run sluggish as you have described. As you may already know, the catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When this 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. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.
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My passenger side window doesn’t work. Put in a new regulator that wasn’t the problem. The window doesn’t go up or down from the
ANSWER : Hi there. It’s possible that an electrical relay is damaged or you have a shorted electrical wire or faulty ground wire that is causing this issue with your motor. It’s also possible that a mechanical arm inside the passenger side door is bent. Before you start replacing more parts, it’s probably a better idea to have a professional mechanic complete a power window not working inspection, so they can pinpoint the source and recommend the right repairs.
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On the driver side of my car the low beam headlight doesn’t work. I checked all fuses and changed the bulb, but it still doesn’t work
ANSWER : Hey there. When you say you checked the fuses & the relays, and everything was getting power, did you check the actual outlet for power? You can use a voltmeter to test the available voltage at the bulb socket. You can also use an ohmmeter to test the resistance of the socket and make sure the socket itself has not failed. If this is the case, you will need to rewire a new bulb socket into place. If performing this at home, your main concern should be with making sure the new connections are protected from the environment. If you do not have the right amount of available voltage at the socket, you will want to trace from the fuses and relays to the socket every foot or so until you find where the voltage drop occurs. This is where your issue is and it must be corrected by whatever means necessary, which can only be determined once the issue was found. You may have a short or a damaged wire/connection along the way. If you would like to have this taken care of, a qualified professional, like one from YourMechanic, can come to your car’s location to diagnose the headlight problem and follow through with repairs.
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My AC is only blowing through the defrost vent and rear defrost doesn’t work.
ANSWER : Hi there. The blend doors on your vehicle are operated by a vacuum hose. Check the vacuum lines to the engine and see if any of them are broken, has a hole, or is disconnected. Check the vacuum hose on the blend door and see if it has came off or broke. For the rear defroster, check the switch to the defroster and make sure that it has power to it and power coming out. If there is no power to the switch, then check the fuses and see if any of them are blown. The rear defroster has a blend door that opens and closes that is electronically. If the fuse is blown, either the switch has failed or the blend door motor has failed. If you need further assistance with your vehicle, then seek out a professional, such as one from Your Mechanic, to help you with your defroster vents not blowing air.
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My car wont start and doesn’t do anything when i turn the key only the lights come on, 1999 Nissan Altima
ANSWER : It sounds like you may need a starter. The testing for it is pretty straightforward. Check the battery cable going to it, and check for power at the start wire. If there is power at both, it will need a starter. If there is not power at the start wire, when the key is in the start position, that circuit will need to be inspected. A mobile mechanic, such as one from YourMechanic, can come to your car’s location to diagnose and repair your starting issue, if you still need assistance.
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Car doesn’t accelerate
ANSWER : This may be a sign of a faulty MAP sensor as the vehicle responds adversely to a load put on the motor (i.e. putting it in gear, turning on AC or engaging the brakes). The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the MAP sensor, it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.
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