Rattling heard and felt from underneath car when accelerating. Car hesitates (as if it will cut off) when accelerating
I feel knocking underneath car and also hear/feel rambles from beneath when I take off from stop or accelerate. My car hesitates as if it will cut off when accelerating from stop. The 'Put-Put' also occurs when accelerating on the highway.
The traction indicator light is illuminating.
The service engine light is illuminating
My car has 65000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hi, thanks for writing in. Sorry to hear of your difficulty with your 2012 Sonic. The good news is your Check Engine Light is on, so what means the fault has been "recorded" by the engine computer and diagnostic codes will be available to the mechanic to search for the fault. The codes don’t necessarily indicate which "parts" have failed but rather will indicate which systems are malfunctioning and causing poor operation of the engine. Individual components in these systems will then have to be tested by the mechanic. The traction codes may or may not be related to the issue with the engine, the poor acceleration, but those traction codes will have to be evaluated as well. It is possible there is more than one problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect your vehicle for you and download codes your car computer has stored, and make or suggest any repairs as needed.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
Key Takeaway Rattling noises when accelerating can be caused by a number of issues, including damaged or worn-out suspension components, bad wheel bearings, low transmission fluid, loose heat shields, and faulty engine components.
Wondering why your car feels sluggish when accelerating? It could be due to a dirty air filter, a bad spark plug, or a faulty catalytic converter — among several potential suspects behind sluggish acceleration.
Rattles From Under the Car
Two common sources of these troubling sounds are the exhaust and emissions systems. Again, it`s wise to look at the least-expensive problems first, and in this case, the least expensive problem is with a heat shield.
When you press down the accelerator pedal and get minimal output, it could mean you have a problem with your fuel system. The most probable issue is a clogged fuel filter. Your fuel filter works to ensure that dirt and debris do not get into the fuel system.
If you hear a rattling noise while driving, the first step is to not ignore it. The sounds and vibrations coming from your vehicle could be signs of a serious mechanical issue. Seek help from a professional who can find the source of the noise before any further damage is done.
If the rattle just started after putting on the summer tires, check for loose wheel covers. Check wheel well plastic liners and underbody panels, especially those connected to the lower edge of the front bumper cover. Check the exhaust system; are any hangers or clamps loose or broken.
It sounds like a light knocking or growling sound. Gear rattle is an audible noise transmitted from the impacts between the transmission gear teeth. A vehicle engine`s torsional vibrations (momentary angular acceleration) pass through a transmission causing the separation and resulting impact of the gear teeth.
Rattling Noise – Once your catalytic converter becomes older or damaged from fuel mixtures, the honeycombs on the inside can begin to collapse and/or break apart which will cause a rattle to occur.
When your engine is lubricated properly with fresh oil, it should run fairly quietly. As the oil ages and it loses its ability to lubricate the components, the parts will start to move harder against one another causing friction and grinding. These rattling, rumbling, and knocking noises will be hard to miss.
This hesitation while accelerating can be the result of a number of issues, including something like a clogged fuel filter or even a broken fuel pump. Sometimes, something could also be wrong with the transmission.
The accelerator pedal sensor transmits the position of the accelerator pedal to the engine control unit. Based on this information, the load requested by the driver can be implemented immediately.
(1) An accelerometer is an electromechanical sensor that measures static and/or dynamic acceleration forces acting upon an object by measuring the acceleration (the rate of change of velocity) along one, two, or three axes.
Poor Engine Performance
You bet. Moreover, you may also notice poor acceleration, engine misfires, and even stalling. Bad oxygen sensors disrupt all kinds of essential engine functions, including engine timing, combustion intervals, and air-fuel ratio.
What is BSR testing? Buzz, squeak and rattle (BSR) testing utilises real life data files to simulate different road profiles which helps to isolate the causes of unwanted audible noises in an automobile. The road simulations therefore are able to provide repeatability during testing.
Your gearbox may be malfunctioning if you hear unusual noises coming from it. Listen out for whining, banging and clunking. However, these noises may be caused by other problems, perhaps a faulty engine, drive shaft or exhaust. Nonetheless, it will be time for a trip to the garage.
Driving with A Failed Catalytic Converter
If you`re noticing slow powertrain performance, reduced acceleration, a smell of rotten eggs or sulfur from the exhaust, dark exhaust smoke, or extreme heat from under the vehicle, these are symptoms of a clogged Catalytic Converter, and it should be replaced quickly.
The first sign of a stolen catalytic converter is incredibly loud vehicle noises. You will find that when driving without your catalytic converter, it will sound like your vehicle is roaring—especially when starting or giving it gas.
When the spark plugs malfunction, they reduce the effectiveness of the engine`s cylinders, which then causes the cylinders to rattle. These unpleasant noises indicate that the cylinders are being overworked and will lead to further troubles down the line.
Has my car problem been fixed? This could cause momentary engine rattling, which goes away once enough oil is pumped from the sump. It should go away once you replace the oil with one of the right viscosity.
Trouble accelerating can come from a few different engine issues. These include, but are not limited to, dirty fuel injectors, low fuel pressure, and restricted airflow. A problem with the mass airflow sensor, throttle position sensor, or engine speed sensor can also cause a car to have difficulty picking up speed.
One of the most common causes of a sputtering engine is an issue with the vehicle`s fuel system—the filter, pump, and injectors. These three critical components work together to ensure fuel flows smoothly from the fuel tank to your engine`s fuel injectors, and then pumps into the engine evenly.
Rough starts, hesitation and poor acceleration are all common symptoms of a bad spark plug. If a spark plug or multiple spark plugs are faulty, they will have trouble creating the spark that causes the ignition process in your vehicle.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Rattling heard and felt from underneath car when accelerating. Car hesitates (as if it will cut off) when accelerating
ANSWER : Hi, thanks for writing in. Sorry to hear of your difficulty with your 2012 Sonic. The good news is your Check Engine Light is on, so what means the fault has been "recorded" by the engine computer and diagnostic codes will be available to the mechanic to search for the fault. The codes don’t necessarily indicate which "parts" have failed but rather will indicate which systems are malfunctioning and causing poor operation of the engine. Individual components in these systems will then have to be tested by the mechanic. The traction codes may or may not be related to the issue with the engine, the poor acceleration, but those traction codes will have to be evaluated as well. It is possible there is more than one problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect your vehicle for you and download codes your car computer has stored, and make or suggest any repairs as needed.
The car accelerates slowly, hesitates and shudders
ANSWER : Unmetered air can cause this type of hesitation and shuddering. Too much air compared to fuel will cause a lean misfiring condition. Fault codes need to be read out of your Mercedes C320’s engine computer to see if there are any underlying issues and those issues are corrected.
The induction should be inspected and checked for vacuum leaks. Also, fuel pressure and volume should be checked as well if the induction system checks out okay. A partially clogged fuel filter can cause a starvation issue on heavy acceleration. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and expertise to conduct this type of diagnosis and repair for your acceleration issue.
i was driving and my oil light kept going off. Car had oil. Car wouldn’t accelerate. Car died. It does not turn engine over now.
ANSWER : It is very possible that the engine has been damaged beyond repair. Usually when the oil light goes on and the vehicle is low on oil, especially when a loud noise is heard right before the vehicle died, it is very likely that the engine is blown and would require replacement in order to continue driving the vehicle. I would recommend having the vehicle checked with a no start inspection. Consider YourMechanic as this service can be completed at your home or office.
car surges when idle or in park. rpm bounce. car has cut off, but cuts back on.
ANSWER : It sounds like your idle air control valve could be failing. The idle air control valve is responsible for maintaining the proper amount of air into the intake while the vehicle is slowing down to a stop and resuming idle speed. When this valve fails, it can cause the exact symptoms that you described. I would recommend having the idle air control valve inspected by a qualified professional to determine if it is performing properly. If the IAC valve has failed, I would recommend having it replaced at your earliest opportunity.
My car will cut out while driving (acceleration cuts out) & car will stop running
ANSWER : Hello. Being that this is a computer controlled vehicle this can be caused by a number of issues. From what you are explaining though it sounds like you have a fuel system problem. Most of the time this occurs if the fuel pump is overheating or if there is a circuit issue. It can be the computer also but that is not as common. One other common part that will fail is the main relay, as when it fails it will disconnect power from vital powertrain circuits and this will occur. I usually scan the computer for codes first to see if any issues show up. If not then I would use my scan tool to monitor all of the sensor readings to make sure that none of them are reading incorrectly. If all of those are fine, then I check the fuel pressure and the circuit to see if it is losing power from the relay and to see if the fuel pressure is dropping indicating a failing fuel pump. If you are going to have this stalling and power loss problem looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.
My Traction control Light Comes on and the car stops accelerating After cutting the car off for 15 to 20 minutes it starts back up
ANSWER : Hi There,
It sounds like you may have a faulty traction control module. When the car shuts off and sits for 15-20 minutes as you describe, this gives the module time to reset itself which then allows you to drive again with normal functionality until it detects the problem again. Once it does, this process repeats itself. The traction control system monitors the steering stability of the vehicle and engages when loss of traction has been detected. This is done by the use of electronic sensors at each of the four wheels that communicate with the Powertrain Control Module (PCM) regarding steering performance and stability in adverse weather conditions. The traction control system works by reducing engine speed and determining which wheel to apply brake pressure to in order to prevent the vehicle from sliding. The anti-lock braking system and the traction control system work together to maintain the stability of the vehicle. The computer uses this information received from electronic sensors regarding the rotational speed of each wheel, the horizontal motion of the vehicle, and the vertical motion of the vehicle to determine how to direct the traction control system or the anti-lock braking system to best control the vehicle when needed. When this warning indicator light comes on in the dashboard, this could be an indication of several issues such as faulty wheel speed sensors, a faulty steering angle sensor, a faulty rotational speed sensor or a problem with the steering rack. In some cases, the traction control system may simply need to be reprogrammed. I would recommend having a professional from YourMechanic come to your location to properly diagnose your traction control system.
It sounds like you may have a faulty traction control module. When the car shuts off and sits for 15-20 minutes as you describe, this gives the module time to reset itself which then allows you to drive again with normal functionality until it detects the problem again. Once it does, this process repeats itself. The traction control system monitors the steering stability of the vehicle and engages when loss of traction has been detected. This is done by the use of electronic sensors at each of the four wheels that communicate with the Powertrain Control Module (PCM) regarding steering performance and stability in adverse weather conditions. The traction control system works by reducing engine speed and determining which wheel to apply brake pressure to in order to prevent the vehicle from sliding. The anti-lock braking system and the traction control system work together to maintain the stability of the vehicle. The computer uses this information received from electronic sensors regarding the rotational speed of each wheel, the horizontal motion of the vehicle, and the vertical motion of the vehicle to determine how to direct the traction control system or the anti-lock braking system to best control the vehicle when needed. When this warning indicator light comes on in the dashboard, this could be an indication of several issues such as faulty wheel speed sensors, a faulty steering angle sensor, a faulty rotational speed sensor or a problem with the steering rack. In some cases, the traction control system may simply need to be reprogrammed. I would recommend having a professional from YourMechanic come to your location to properly diagnose your traction control system.
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
My car is not driving smooth as I feel hard acceleration but only at low speed i.e 40 km/hr
ANSWER : Hi there. This presents an interesting situation and I completely understand how you feel. It’s almost like now that something has gone wrong, you wonder what else is going wrong with the car? And it doesn’t feel like it should. More often than not, there may not be anything going on except in our own mind; we never seem to notice much until something happens. And you’re right to try to get to the bottom of it.
I have to ask first, why was the compressor bearing replaced? When you were driving through the rain, what type of noise did you hear? If it was a squealing noise, then it may have simply been water that had gotten onto the serpentine belt while driving in the rain. However, I still do not know why a compressor bearing was replaced. As for the low "grrr" sound, this could simply be a resonation from the AC tubes if they were repositioned during the repair.
I have also experienced Toyotas that develop a similar sound or low rattle type sound under moderate acceleration from the exhaust manifold heat shields and/or the intake manifold bolt hole inserts becoming loose. This wouldn’t necessarily be a safety or engine performance concern, but would definitely make you feel like it is. Be sure to have a professional mechanic, such as one from YourMechanic, perform an inspection to determine what repairs are needed.
