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Q: Idles and stalls again.

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Car idles really rough, but when you get it out on the road at higher speeds it almost completely clears up. then when you slow down to stop at stop sign it almost doesnt stay running its idling so badly. put new injectors in it but didnt help . almost made it worse. Also ABS light wont go off. The breaks have all been serviced but the light on the dash wont stop flashing the word STOP at me and ABS.

My car has 200000 miles.
My car has an automatic transmission.

Hi There, It sounds lik eyou have two separate issues going on here. The ABS light is likely related to the [wheel speed sensors]((https://www.yourmechanic.com/services/abs-speed-sensor-replacement) which help to control the ABS system. It is quite likely that these may have been disturbed when the brakes were changed. Your car is equipped with wheel speed sensors at each of the four wheels which monitor wheel speed while relaying this information constantly to the ABS and traction control system which are controlled by the car’s ECU. When the ECU senses an abnormal speed given specific conditions, it engages the ABS or traction control as needed to control the vehicle properly and safely.

The rough idle you are describing is commonly related to a dirty or faulty idle control valve. The idle air control valve monitors 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 and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. 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 while adjusting the air/fuel ratio constantly to allow this to happen smoothly. 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 inspect your vehicle.

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