Q: Replaced throttle body high idle

asked by on April 13, 2017

Just replaced the Throttle body, Upon start up the vehicle goes into a overwhelmingly high idle, Like someone is stepping on the pedal, When drop down into park the idle lowers but is still very high, Please advise
My car has an automatic transmission.

Hi There, As you may know, after cleaning the throttle body your car needs to go through a "re-learning" process to bring the idle back down. Try doing the following which should bring the idle back down to a normal operating level:

1) Start the engine and let it idle in park for 3 minutes. During that period the idle may be higher idle than normal. 2) After 3 minutes, turn the engine off and leave it off for 60- seconds. 3) Start the engine again and let it idle in park for 3 minutes one more time. During these run periods you may see a check engine light. Scan for codes and if you get throttle body related codes, clear them. 4) If the idle speed is still off, drive the vehicle at speeds above 45-mph and operate several acceleration and deceleration cycles. Then repeat step #3 one last time.

This should bring your idle back down to normal. Should you need further help with this, please reach out to us here at YourMechanic as we are always here to help.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

How do I fold the side mirrors on a 2012 Toyota Corolla?
The side mirrors can be folded in towards the car, to help protect them, or to lower the width of the vehicle. To fold the mirrors, simply grab them and push them toward the side windows until they fold into...
ABS light and brake lights are on all the time
This indicates there is a problem in the Anti-Lock Braking System (ABS). In this system, the VSA modulator control unit monitors wheel speed via sensors. If from the sensor signals the module determines wheel lockup is about to take place,...
Won't drive forward only reverse
Hello...there is a fault in the transmission of course. However, check your transmission fluid level first. If fluid is REALLY low, you could have an issue like this. There is a mechanical linkage in play when you shift into drive....
My car will only turn on when my foot is on the gas but turns off when its not
Hey there. This could be from a couple of potential problems. Your car has what is called a throttle position sensor (https://www.yourmechanic.com/services/throttle-position-sensor-replacement) which monitors the position of your foot on the gas pedal and relays this to the computer which...
Check engine light P0302
Hello there, thanks for your question. I'd be happy to help. It does sound like a bad ignition coil (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-ignition-coil) is the cause of this P0302 trouble code (https://www.yourmechanic.com/article/p0302-obd-ii-trouble-code-cylinder-2-misfire-detected-by-jamahl-walker). This is not uncommon since your car has over 100,000 miles....
Getting the code P0500. Changed both NC & NT sensors. Can't pull out the vehicle speed sensor (VSS).
Hi there. The code P0500 (https://www.yourmechanic.com/article/p0500-obd-ii-trouble-code-vehicle-speed-sensor-malfunction-by-spencer-clayton) is in reference with the vehicle speed sensor. The possible causes that contribute for this code to appear are: The vehicle speed sensor (VSS) is not reading properly There is a broken or frayed...
Do I need a new transmission?
The leak might be transmission fluid. If the transmission has been leaking for a while, the fluid level could have fallen low enough to cause engagement and shift difficulties. Therefore, you should first check the fluid level. If low, add...
P0302 misfire, car won;t go past 25 mph
I am not sure if the mechanic who replaced your head ran a compression test after the head was replaced but if not I can think of a couple of possibilities both of which lead back to low compression. The...
How long will a car with 180000
Hi there. It really depends on how well the vehicle was maintained before you purchased the vehicle, how it was driven and how well you keep up with recommended service and maintenance that will indicate how long the vehicle will...

Related articles

The Best Used Cars to Buy If You Just Retired
Here’s Here’s a cruel, hard fact – car manufacturers no longer target seniors. Instead, they devote their time and energy to appealing to the 18-45 demographic. Still, some features make certain cars more suitable for older drivers. We have evaluated...
The Best Used Cars to Buy for Dog Owners
Dog Dog owners are a special breed of drivers. When they shop for a used car they have a list of requirements that can be quite different from other drivers, which tends to make the process a bit of a...
How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It is a five-button numeric keypad that is used to: Eliminate fumbling...