P0518 OBD-II Trouble Code: Idle Air Control Circuit Intermittent

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0518 code

P0518 is a diagnostic trouble code (DTC) for "Idle Air Control Circuit Intermittent". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$20.00
Toyota$20.00
BMW$20.00
SCHEDULE P0518 DIAGNOSTIC Get a fair and transparent estimate upfront

Diagnostic Trouble Code (DTC): P0518

P0518 code definition

If the PCM has registered an inconsistency in the engine idle RPM; the P0518 code will be stored.

What the P0518 code means

The manufacturer of the vehicle has set an expected RPM that must be registered when the engine is idling. The PCM will read the RPM during idle; if the reading is too high or too low in comparison to the manufacturer’s specifications, the PCM will try to correct the issue by sending commands to various parts of the engine and transmission. If the RPM is not corrected, the PCM will store the P0518 code.

What causes the P0518 code?

This code is very frequently caused by a carbon choked throttle body bore. Other causes may include:

What are the symptoms of the P0518 code?

There are several symptoms that a vehicle owner may observe when the P0518 code is stored, including:

How does a mechanic diagnose the P0518 code?

After an OBD-II scanner detects the P0518 code, a technician should begin with a visual inspection of all electrical components: replacing, reconnecting, or repairing as necessary. They should then clear the code and perform a test drive, checking that the Check Engine Light does not reappear. If the code does reappear, then the mechanic will disconnect the IAC motor from its electrical connector and start the engine. If the code does not reappear after this step, the IAC valve likely has a short, and is to blame.

If this diagnostic step did not uncover the problem, then the mechanic must continue checking the system for various electrical issues until the problem is discovered.

Common mistakes when diagnosing the P0518 code

Many technicians have reported that it is common for the idle air control components to be replaced before the throttle body bore is cleaned; this can lead to wasted money and repair time. It is important to attempt the basic repairs, such as replacing electrical wiring or cleaning the throttle body bore, before replacing major components. It is also important to clear the code and do a road test after each potential solution is attempted. If the most common repairs do not stop the Check Engine Light from reappearing, it can be a sign of an intermittent issue that requires an in-depth inspection and servicing.

How serious is the P0518 code?

If the P0518 code is being detected, the vehicle needs to be repaired as soon as possible. This code indicates an issue that affects the immediate drivability and safety of the vehicle.

What repairs can fix the P0518 code?

For the most part, addressing the P0518 code means fixing faulty electrical components; however, there are other repairs that may need to be done to clear this code entirely. They include:

Need help with a P0518 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

pcm
trouble codes
Check Engine Light
engine idle

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0518 code.

SCHEDULE P0518 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.8/5

Number of Reviews

5,064

Rating Summary
4,665
194
48
27
130
4,665
194
48
27
130

Mario

8 years of experience
22 reviews
Mario
8 years of experience
Chrysler PT Cruiser - Check Engine Light is on - Los Angeles, California
He was very courteous and knowledgeable. You can tell he knows his trade. Satisfied with his service.

Yoel

8 years of experience
91 reviews
Yoel
8 years of experience
Nissan Versa Note - Check Engine Light is on - Upper Darby, Pennsylvania
Yoel is very competent and provides great customer service. He took the time to explain and show me exactly what was going with my car. I will definitely use him again and recommend him to others.

Jason

31 years of experience
148 reviews
Jason
31 years of experience
Ford Explorer - Check Engine Light is on - Phoenix, Arizona
Jason was on time, friendly, explained everything he was doing and let me know the other services available, so when Jason comes back to install the new part I am having the oil changed too.

DeVaughn

25 years of experience
1 reviews
DeVaughn
25 years of experience
BMW X3 - Check Engine Light is on - Moreno Valley, California
The mechanic arrived on time, completed the work, which was replacement of an oxygen sensor, in a timely and professional manner.


More related articles

Related questions

Prnds flashing lights anb p0777 code

Hello. For this vehicle, it appears that the solenoids are located inside the transmission. For many vehicles the transmission control solenoids are bolted to the exterior of the transmission, however for this vehicle the solenoids are part of the transmission...

Truck dies when at idle or stopped

It sounds like you may have a dirty or failing 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...

Hi man.. I own a 2007 VW Passat 2.0, I got check engine light showing code p2181 cooling system error. Should I change only the th

Hello. A P2181 cooling system code is really generic, and all it means is that the cooling system is too hot or too cold. Unfortunately that does not give you much to work with. Check the level of your coolant,...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1-800-701-6230 · hi@yourmechanic.com