My car is idling very rough.
Yesterday night my car started idling very rough, so I figured out shortly after that I had little to no oil in the car (my oil indicator doesn't work), and so I filled the car with oil, and thought that would fix the problem because before the only thing that was wrong with my idle before was the idle air control valve which I fixed shortly after getting the car, so after I filled the car with oil then I drove for about 10 minutes and the car was smooth for the first 2 minutes then it would idle very rough at stop lights and stop signs but around 2-3k rpms it would drive smoothly, and I w
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The idle air control valve is common for causing a rough idle in many cars, but it sounds like you have already corrected that. Another thing you may also want to check is the crankshaft position sensor. A crankshaft position sensor monitors the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system timing and other engine parameters. When this is faulty or not working properly, this will cause problems with the ignition system and generating spark transmission to the spark plugs resulting in starting problems, rough idling and other performance issues. You may also want to check the fuel pressure as low fuel pressure can also cause rough or poor idling if the fuel pattern being sprayed from the injectors is not consistent. This can also happen in the case of having dirty fuel injectors which may also interrupt the spray pattern of the injectors. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your car.
How to Identify and Fix Common car Problems ?
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A rough idling engine can be caused by spark plugs or spark plug wires. Spark plugs use the electrical current received from ignition coils to ignite the air/fuel mixture within the combustion chamber. A plug that is damaged or installed incorrectly can result in fuel being burned at an inconsistent rate.
How to fix it? Cleaning or replacing the fuel filter and adding a fuel injector cleaning treatment to the fuel tank should take care of clogged fuel injectors. If the rough idle persists, it`s time to take your car to an auto repair shop.
Typically, the idle speed will be set at a value in the range of 600 to 800 RPM, but the exact value will depend on the number of engine cylinders and whether the vehicle is equipped with a manual or automatic transmission.
While it may seem like a small problem on its own, rough idling is a sign that some part of your engine isn`t working properly. Over time, rough idling can result in poor gas mileage, starting issues and major engine problems.
Engine Misfires
Perhaps the single most common cause of rough idle comes in the form of a misfiring engine. As you may know, any automotive engine contains multiple cylinders. Each of these cylinders contributes to powering your car by combusting a mixture of gasoline and air.
What to Look For: Rough idle, slow acceleration, sputtering or a lack of power on acceleration are all symptoms of a leak in the vacuum system. Faulty EGR Valve – The EGR valve is responsible for recirculating exhaust fumes back into the combustion system.
Simply put, a rough idle describes an engine that is not firing consistently when your vehicle is in park, with no gas applied. Most vehicles idle between 600 and 1,200 RPM and should hold their idle speed.
Engine misfires, rough idling and hard starts can all be traced to a clogged engine air filter. The dirty air filter restricts the air supply to the engine causing unburned fuel to form a soot residue that accumulates on the spark plug.
For regular cars, idle speed is typically between 600 and 1,000 rpm, just enough to keep the engine`s ancillary systems going, but not enough to move the car forward much.
Most cars should idle between 600 RPM and 1,000 RPM. Cars that idle below 600 RPM or above 1,000 RPM may have a mechanical issue that you need to address. Additionally, if the RPM jumps around when idling, this also may be a sign of a bigger problem.
Causes of a rough idle. Many different problems could result in a rough idle for your car or truck, including: dirty fuel injectors, clogged air filters, bad spark plugs, and a variety of exhaust system issues.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
My car has a rough idle when I start my car, when I stop at a light my car turns off. Is it the purge sensor?
ANSWER : This may be a result of a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. Since this valve is controlled by the vehicle’s computer, it will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your idle air control valve.
Read Full Q/A … : My car is idling very rough.
My car is idling very rough.
ANSWER : The idle air control valve is common for causing a rough idle in many cars, but it sounds like you have already corrected that. Another thing you may also want to check is the crankshaft position sensor. A crankshaft position sensor monitors the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system timing and other engine parameters. When this is faulty or not working properly, this will cause problems with the ignition system and generating spark transmission to the spark plugs resulting in starting problems, rough idling and other performance issues. You may also want to check the fuel pressure as low fuel pressure can also cause rough or poor idling if the fuel pattern being sprayed from the injectors is not consistent. This can also happen in the case of having dirty fuel injectors which may also interrupt the spray pattern of the injectors. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your car.
Read Full Q/A … : My car is idling very rough.
My car started idleing rough, vibrations soon as start car, vibrations soon as I accelerate, vibrations, rough idle bad
ANSWER : This sound like you may be having an engine misfire. Have the system checked and scanned to see if codes are present for an engine misfire. If it is, then a mechanic can check to see if a coil or spark plug has failed. You may have oil leaks in the valve cover seals that has caused the ignition to short out in the spark plug holes. A repair of your valve cover gaskets may be necessary, along with the other components that I’ve mentioned. I’d recommend having the vehicle looked at by a qualified technician who will be able to diagnose these misfiring symptoms and fix it accordingly.
Read Full Q/A … : My car is idling very rough.
Got my rear main seal fixed, but my car keeps having a rough idle, cutting off & the Electronic Throttle Control Light is on.
ANSWER : It sounds like you may have a faulty electronic throttle control unit. The electronic throttle unit opens and closes the throttle blade based upon input from various engine control sensors, including the accelerator pedal. This unit also controls, among other things, the cruise control function as well. When this control unit fails, this may cause intermittent stalling issues and rough idle problems. This is usually repaired by removing and replacing the throtte control unit. I would suggest having an expert from YourMechanic come to your location to diagnose and inspect your vehicle at your earliest convenience.
Read Full Q/A … : My car is idling very rough.
The car idles rough and is shooting out codes p0017, p0016.
ANSWER : Hello. This is a common problem with the variable valve timing solenoid on this engine. I have changed quite a few of these due to failure. I always start by checking the codes and testing the solenoids and the connectors as some of the time the connectors fail and have poor connections. There have been a few times that I have seen these codes due to low oil or the wrong oil and from the camshaft actuators failing, but most of the time it is due to the solenoids. If you are planning on having this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair the rough idling issue for you.
Read Full Q/A … : My car is idling very rough.
My car is idling rough and flooding out when first starting. What could be causing this?
ANSWER : This may be related to a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer which will adjust idle speed based upon other measurements, such as engine temperature, intake air temperature, and electrical system load or voltage.
When you accelerate, the engine RPM increases, and, as you let off the gas, the RPM slowly returns to the normal idling speed. This is all controlled by the idle air control valve. When the engine RPM drops below the normal range of 750-800 RPM, this may indicate a dirty or faulty idle air control valve.
I would recommend having an expert, such as one from YourMechanic, come to your location to determine why the car is running rough and replace your idle air control valve if needed.
Read Full Q/A … : My car is idling very rough.
My car runs rough at idle, stalls at idle, surges, and idles at 40 miles an hour
ANSWER : A number of components or faults can cause your issues. A vacuum leak can cause your issues. Depending on the vehicle, components such as the mass airflow sensor, throttle position sensor, coolant temperature sensor, and a number of others can be the cause. Since randomly replacing parts can get expensive as most electronic components are not returnable once installed, having a certified technician, such as one from YourMechanic, diagnose the stalling/surging is the best place to start.
Read Full Q/A … : My car is idling very rough.
My car had a rough idle, and if I sit at a red light or let the car run in idle for a few minutes my check engine light starts to
ANSWER : A dead misfire on a single cylinder may be deeper than just a spark plug. If the compression for that cylinder is very low, the cylinder cannot fire. Low compression would be caused by worn piston rings. Also, if the fuel injector is leaking or not flowing enough fuel, this may cause a misfire as well if the injector is leaking bad enough. A fouled spark plug usually leads to a coil that is not functioning or lack of compression in that cylinder. If you would like to have this taken care of, a qualified professional from YourMechanic can come to your car’s location to diagnose the rough idle and help you move forward with repairs.
Read Full Q/A … : My car is idling very rough.
