Reasons for a car running rough can include problems with the engine temperature or oxygen sensors, bad hoses, ignition system or timing problems, clogged air or fuel filters, and faulty spark plugs or fuel injectors. Many problems that manifest through a rough idle can be easily fixed.Continue Reading
If the engine temperature sensor fails, it sends the wrong temperature signal, and the result is a fuel mixture that is too lean, which makes the car run rough. As the weather warms up, this is rarely a problem. A failing oxygen sensor can also cause a car to run rough while idling, but it won't affect the car while driving.
A bad hose in any part of the engine is easy to fix. Sometimes, vacuum lines cause a rough idle due to a vacuum leak, and these lines are also simple to replace.
A common cause of an engine running rough is faulty ignition timing. Once the timing is adjusted, the car should run smoothly. The idle speed may also be set too low. Other problems in the ignition system that can cause rough idling include faulty spark plugs, rotors, ignition wires or distributor caps.
Engines have a tough time running smoothly if the fuel or air filters are clogged. These parts are also easy to replace. Dirty fuel injectors must be replaced to keep an engine running well.Learn more about Car Parts & Maintenance
Before electronically-controlled vehicles, a tune-up included maintenance adjustments to the engine and replacement of the spark plugs and distributor points, the distributor cap and rotor, and the fuel and air filters. As of 2014, many newer vehicles have on-board computers that automatically perform maintenance adjustments, so tune-ups aren't necessary.Full Answer >
An electronic ignition system works by using sensors, transistors and electrical switches to deliver high voltage to the engine's spark plugs. This helps the engine generate a stronger spark, which leads to improved combustion and emissions control.Full Answer >
Car tune-ups may entail different actions to ensure cars run smoothly and safely, such as repairing and replacing oil and air filters, adjusting timing belts, inspecting the engine and adjusting the clutch on vehicles with a manual transmission system. Tuneups vary in extensiveness depending on the make and year of the car, along with any indications of problems. Regardless of car, however, technicians perform tune-ups using different diagnostic equipment and tools, which help detect problems.Full Answer >
Most cars have a throttle position sensor, manifold pressure sensor, engine coolant temperature sensor, mass air flow sensor, camshaft and crankshaft position sensors and a oxygen sensor. Automobiles also have detonation sensors, EGR sensors and intake air temperature sensors.Full Answer >