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A vacuume leak at the intake manifold or vacumme hose can cause a high idle. On carbuerated vehicles the idle adjustment screw may be set to high. On fuel injected vehicles, the Idle Air Control(IAC) circuit or valve may be faulty. On newer vehicles you may be able to get a trouble code to help pinpoint the problem. Chris

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โˆ™ 2005-03-19 13:12:46
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Q: Why would a car idle too high?
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Related Questions

What happenes if the Idle speed in a car is too high?

the engine runs at a faster rate than when the idle speed is lower.

What causes a car to surge when you release the brakes?

Idle set too high or accelerator is sticking and needs lubrication.

What could be the problem when you take car to shop to get tune up and other work Now car jerks when put in reverse and drive?

Not knowing exactly what they did my best educated guess would be that the idle is too high.

Why does the car turns off if you are not pushing on the gas?

Check your idle, your idle might be too low so it is stalling your car.

How and where do you change the idle speed on a 1993 Mitsubishi Galant SOHC?

The idle speed is factory pre-set, and no adjustment is available. If the idle is too high, or too low, you will be having other problems that will affect the idle. In cooler temperatures, it will take the engine longer to come out of fast idle, as the engine warms up to operating temp. If the idle is too high/stays at a higher than normal idle, then take the thing to get it repaired. Running a car in gear(automatic transmission) with a higher than normal idle, can damage the transmission.

What does a bad idle mean?

Bad idle may refer to many things. Generally it means the idle is too high, too low, or there are misfires.

Why does a car idle too low?

A car can idle too low because there is a leak in the vacuum. Cracks or breaks on the vacuum hoses in the cars engine could be the cause of this.

What would cause an automatic 95 Celica to Jerk forward when placing it in Drive?

It's possible that the idle speed is set to high or low. When you shift into drive, power is applied from the motor through the transmission to the CV axles. If the idle is set too high there will be too much power applied to a "stopped" car. If the idle is set too low, then when the car is put into drive, the RPMs will drop and the car will apply more gas to keep the engine from stalling. Start your car and watch your tachometer. It will normally start off high (between 1-2k RPMs) then it should lower within a minute. Note the idle RPM. It should be around 1k RPMs (+/- 300 RPMs). If it's outside of that range or if the needle moves a lot, then there's something wrong. You can find the factory spec idle speed online if you look.

Why would a 95 Saturn start with a jerk when put into drive?

Posssibly the idle is too high. TAke the idle solonoid off of the throtle body and clean it.

Why is it that when you turn the car off its still running?

Could be that your idle speed is too high, or engine is running too hot causing the PMC to deliver a richer mixture,

Why would a car stall after it warms up and comes to a stop?

I would suggest that the Choke is switching off and then the idle is set too low

What should I try next on a 89 Pulsar that sometimes idles way too fast- cleaning the injectors didn't help?

If the idle is constantly high, I would adjust the idle control on the left hand side (facing the car) of the throttle control body.

What would cause your transmission to jerk when going from neutral to drive in my 200 Pontiac grand am?

Idle speed too high.

What causes high idle on 91 dodge stealth?

see previous answers, but if it idles high it might be the Mass Airflow Sensor. if your car idles too high for too long and you keep driving it, you could burn out the transmission module (very expensive )

Why does your mower sound too powerful?

Idle adjustment set to high

How do you adjust idle on 1998 ford escort?

You don't. The ECU controls the ISC (Idle Speed Control Motor) which adjusts the idle. If idle is out of control (too low or too high) try gently tapping the ISC with a small (0.5 pound) hammer or a large wrench while the engine is running. If tapping the ISC makes a change in idle speed, you need a new ISC. Clean the throttle body whenever replacing the ISC. If the ISC is not the problem, look for vacuum leaks which can cause both high and low idle. Low coolant level can cause high idle. Also, note that many clueless drivers assume that the idle is wrong (high) when the car is just using high idle (normally) for a short time after a cold start especially in cold weather.

Why does your Kawasaki prairie miss at high idling?

Too high of an idle could be producing too much fuel for your jets to work with

How do you adjust the idle on a 2003 Dodge Durango 4.7L engine?

Idle speed is not adjustable. It is controlled by the engine copmuter. If your idle speed is too high or low you have a problem with a sensor or the idle air controll actuator. Also, a weak battery can cause the idle too be erratic

What makes a 1995 Sonata idle too high?

You may have leak in the intake

Why is the Oldsmobile aurora idle too high?

check intake plenum boot

Why your car stalls when you turn the AC on?

The idle is set too low or there is an electrical problem

How do you adjust the idle on 1984 Corvette?

the 84 uses an idle air control valve to control idle speed. this is a function done by the computer. if the idle is too low when cold but runs ok when hot, or ok when cold but then too high when hot, then chances are your idle air control valve is bad. if the idle is high all the time, you probably have your pcv valve vacuum line disconnected. if your brakes seem very hard to push as well, then it's probably your brake booster vacuum line. if neither of those, look for other vacuum hoses that may be disconnected. there is no user adjustable idle speed control for that car.

Why would a 1995 Mercury Grand Marquis have high idle?

Try adjusting the idle using the idle screw on the butterfly valve of the air intake. It might be that the idle is just set too high. If that doesn't work, try adjusting the timing. If that still doesn't work, try replacing the Throttle Position Sensor, located right above the throttle body.

What is the Idle speed on a 2006 Heritage Softail Classic?

Do you mean the rpm's on the tach? The bike should not run down the road at idle. At idle, in gear it should jump forward and die. If not, the idle is too high.

What is OBD code P0507?

P0507 : Idle control system, RPM too high.