Cars & Vehicles
Auto Parts and Repairs
Fuel and Engines
Car Stalling Problems

What would cause engine to idle rough and die when car slows down or stops?

Top Answer
User Avatar
Wiki User
Answered 2007-06-09 19:17:41

It depends on what kind of car you have. Three things are needed to "make fire" in the engine: fuel, air, and spark. If any of these is interupted then it can sputter or just not run. How those three gets there depends on the car. Older, carbureted engines mixed fuel and air in the carburetor and then moved them into the piston. Fuel interuptions would happen at the carburetor. Air interuptions rarely happened, but could be because of poor settings inside the carburetor. In newer engines the air and fuel are brought in separately. A sticky fuel injector, low fuel pressure, or a computer problem can cause rough idling. How the "spark" gets into the cylinder, via spark plug, has not changed much. What triggers the spark has. In older cars it could be a mechanical distributor/rotor/points system. If there were debris in there, or even poor spacing then the engine could rough-idle. In the newer systems its all computer controlled or hybrid. It could have a weak or discharged battery. It could have a weak alternator/generator. It could have a clogged air or fuel filter. There are a lot of things it can be. A quick inspection can tell a qualified mechanic what the problem is. How he goes about determining what the problem is and how to fix it really depends on the type of Car.

It could be something as simple as a fuel filter! Try that.
Then spark plugs and wires. Air filter.

If those check out fine or you have replaced them. Check for stored trouble codes or an illuminated CEL.

It could also be a Idle Air Controller problem, if they get dirty they can stick. Also, on computerized cars, crank and cam angle sensors can go bad. Lots of things here.

User Avatar

Your Answer


Still have questions?

Related Questions

Why is it important for the roadways to have rough surface?

Roads have rough surfaces because it cause more friction which a) slows down the car and b) because it stops the car swerving as much.

Which substances cause noninfected cells to form an antiviral protein that slows or stops viral multiplication?


What is a force that slows or stops motion when objects rub together?

Friction slows or stops motion when objects rub together.

What force slows and stops?


What is is the special force which stops things moving or which slows down moving things?

friction stops things from moving and slows it down

What is the cause of a loud whining noise when a 2000 Buick LeSabre speeds up but stops when it slows down?

Bad wheel bearing.

What stops radiation?

Nothing actually stops radiation, but lead slows it from spreading around.

What happens to the reaction as a reactant gets used up?

It slows and then stops.

Does a refrigerator stops the food from rotting or it slows down rotting?

I think a refrigerator, slows down the process of food rotting as the microorganisms take more time to cause chemical reactions in cold weather.

When a person stops pedaling the bicycle slows down what force is this?

On a level surface it is rolling friction. If you arte going uphill it is gravity plus rolling friction

Agent that slows or stops the growth of bacteria?


Agent slows or stops the growth of bacteria?


What is a force that slows or stops motion?

Friction, Gravitational force

What is a substance that slows down or stops a chemical reaction?


What is force that slows down or stops something called?


How does rock affect water flow?

it slows /stops the flow

What is the force that slows down or stops the motion of a bicycle?


What is a substance that stops or slows down chemical reactions?

an inhibitor

What material stops or slows the movement of electricity or heat?


What is the substance that slows down or stops a chemical reaction called?

Negative catalysts are substances which slows down chemical reactions.

The car slows then stops?

is it full of petrol ? otherwise it won't work

Force that slows or stops motion?

an opposing force i.e. friction.

The part of the Earth that stops or slows down seismic waves?


What is the force that slows down or stops the motion of an object called?


What is the force that slows down or stops the motion of an object?

Gravitational force .