Q: Hello i have a high idle in the morning when it warms up acting like its going to die

asked by on

high idle in the morning when it warms up it search for the idle almost dies

My car has 61000 miles.
My car has an automatic transmission.

This may be a sign of a vacuum leak. High idle speeds or in some cases rough idle, stalling and hissing sounds are common signs of a vacuum leak. When a vacuum leak is present in an engine, this causes an excessive imbalance in the air/fuel ratio which creates a loss of power and causes the motor to run at a much higher RPM as a result of the increased oxygen present in the fuel charge being injected into the motor. The other possibility may be a dirty or faulty idle air 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.

You can test the functionality of the valve by checking its electrical resistance if you have access to an ohm meter. To do this, disconnect the IAC valve, connect an ohmmeter to pins 2 and 3 of the valve. If you get a resistance value between 10-14 ohms, it indicates IAC valve is working as it should. Next, connect the ohmmeter to pins 1 and 2. If you do not get a resistance value between 10-14 ohms, the IAC valve may need to be replaced. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Hello i have a high idle in the morning when it warms up acting like its going to die

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Check engine light on due to gas cap.

You should have your fuel vapor control system for leaks by a mechanic that can fill the system with smoke from a smoke machine that helps to locate the leak in the system. The purge control valve is the most...

Q: My car started to make a howling noise. A service center said it needs a new driveshaft i.e. Propeller shaft. There is no vibration.

Hi there. Your vehicle has CV shafts that drive the wheels. A howling noise is more of a wheel bearing grinding sound. Raise up the vehicle and rotate all 4 wheels and listen to there sounds. If a wheel is...

Q: Rear brake squealing noise goes off when brakes applied.

Hey there. If the noise was not there before you replaced the brake pads on your 2014 Audi A4, you might want to try replacing the caliper clips and using a good quality brake lube anywhere the pads make contact...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.