P0507: Idle Control System RPM Higher Than Expected

Did the P0507 code pop up on your car scanner? Do you wonder what that means to your car’s performance and driving experience?

Continue reading to have a first evaluation of the issue.

  • P0507 Definition: Idle control system RPM higher than expected
  • Code Type: Generic – P0507 indicates the same problem whether you’re having a Nissan, Chevy, or Honda, etc.
  • Can I drive with the P0507 code? Yes, but it is better to fix it as soon as possible.
  • Easy to fix? Intermediate to advanced level.
  • Cost: $10 – $200 (common)

Problems that throw the P0507 code are less severe and may not disrupt driving. Regardless, they still require attention.

To save time and money on troubleshooting, let’s discuss the five causes of the P0507 error code, some common symptoms, and their solutions.


Table Of Contents


What Does the P0507 Code Mean?

The P0507 is a generic diagnostic code implying that a car engine’s idling speed is at least 200 RPM higher than expected.

Although variations may exist based on manufacturer and model, the standard engine idle speed is between 600 and 800 RPM. Idle speed may also depend on the car features in use, e.g., air conditioning.

When the RPM is higher than usual, the P0507 code and “check engine light” is activated. Driving is still possible as the severity of this issue is low. However, this will decrease your fuel economy.

p0507 causes, symptoms and how to fix

P0507 Causes Identification: Quick View

The following table shows the causes and possible solutions of the P0507 diagnostic trouble code. 

SymptomsCausesSolutions
P0507 Only Stuck-open IAC valve

Stuck-open throttle body/ETC actuator



Bad PCM
Clean or replace the IAC valve

- Clean the throttle body/ETC actuator
- Readjust the throttle cable
- Replace the throttle body/ETC actuator

Replace the PCM
P0507 + Hissing soundVacuum leak (most common)Use smoke test and fix the vacuum leak
P0507 + Presence of engine oil in PCV valve or hoseStuck-open PCV ValveReplace the PCV valve

Note: The causes for each code combination are the most common ones. There can be some uncommon issues hidden under those codes.


P0507: Causes, Symptoms, And How to Fix

Every diagnostic code has one or more root causes that are traceable to some failing or damaged components. For the P0507 code, adequate inspection based on the symptoms is essential.

Here are the familiar causes, symptoms, and solutions of the P0507 code.

Cause #1: Vacuum Leak

When there is a vacuum leak, an additional amount of air enters the system, disrupting the calculated air-fuel ratio.

The result is a higher RPM while idling because there is more air supply than expected. The more air, the more fuel will be added (in order to compensate for the excessive air), leading to higher RPM.

Symptoms of vacuum leak causing P0507:

  • Hissing sound (most common and obvious sign)
  • High long-term fuel trim on both bank 1 and 2 (LTFT1 & LTFT2 >10%)
  • Poor acceleration
  • Engine misfires
  • Check engine light

The common instances of vacuum leak are a faulty intake manifold gasket, damaged vacuum hose, or throttle body gasket. You can use a smoke test to identify the leak and replace any cracked parts.

If you can’t afford a smoke machine, try this $15 DIY smoke machine with Treats On The Streets.

Cause #2: Stuck-open IAC Valve

Typically, the IAC valve allows the air to enter when the throttle plate is closed.

Sometimes, an IAC valve can become stuck-open, letting more air in the system than required. The valve can get jammed due to these two primary reasons:

  • Carbon build-up in the valve opening
  • Faulty IAC circuit 

Symptoms of a stuck-open IAC valve causing P0507:

  • Rough engine idle
  • Irregular idle speed
  • Engine stalling
  • Check engine light

If contaminants are in the IAC valve, cleaning it might end the P0507 code. If that does not work, the last option is to replace the valve entirely.

In this 4-minute video, you can learn how to clean the dirty IAC valve and replace it if this is the last option.

Cause #3: Stuck-open Throttle Body/ ETC actuator

Another possible cause of the P0507 code is a stuck-open throttle body or electronic throttle control (ETC) actuator. Both components control the speed of the engine, subject to the driver’s input from the gas pedal.

Older cars rely on a cable and modern cars use the ETC actuator to control airflow through the throttle valve. 

If the butterfly valve in the throttle body is stuck-open, more air goes into the engine. Subsequently, it disturbs the predetermined engine idle speed.

There are three familiar reasons for a stuck-open throttle Body/ ETC actuator:

  • Carbon build-up (old and new cars)
  • Tight throttle cable (old cars).
  • Faulty throttle body (old cars)/ETC actuator motor (new cars)

Symptoms of a stuck-open throttle body/ETC actuator causing P0507:

  • Rough idle
  • Check engine light
  • Misfires
  • Poor engine performance
  • Stalling

Examining the car properly before making any repairs or replacements is essential. The possible solutions are cleaning the throttle body or ETC actuator, readjusting the throttle cable, or both.

In some cases, a replacement of the throttle body and ETC actuator is necessary.

Another video from Scotty Kilmer on how to replace an electronic throttle.

Cause #4: Stuck-open PCV Valve

The PCV valve manages gasses leaking from the combustion chamber to the crankcase of an engine.

This valve opens to vent the gasses into the intake for combustion to keep the pressure low in the crankcase. Under normal conditions, the PCV valve is closed when an engine idles.

The idle RPM is higher if the PCV valve becomes stuck-open and more crankcase gasses enter the combustion chamber. Sometimes, it may be due to a disconnected hose near the PCV valve.

Symptoms of a stuck-open PCV valve causing P0507:

  • Engine oil in PCV valve or hose
  • Check engine light
  • Lean mixture
  • Misfires
  • Rough acceleration

In the case of a disconnected hose, examine (with the port) before refixing. If the PCV valve is bad, purchase a suitable replacement.

A comprehensive video to guide you to replace the PCV valve from O’Reilly Auto Parts.

Cause #5: Bad PCM (rare)

Although rare, a bad powertrain control module (PCM) can constitute problems that can trigger the P0507 code. This module controls the air-fuel balance of the engine.

When it becomes faulty, the idle air control system and other systems associated with air-fuel supply may receive wrong commands. The check engine light will remain active even after replacing other components.

It is impossible to repair the PCM. Hence, the only solution is a replacement, preferably from the manufacturer.


How Much Does It Cost to Fix P0507?

The total repair expenses depend on the cost of failing or damaged components. A vacuum leak is the most common cause leading to the P0507 popping up. You will spend between $10 – $200 to repair a vacuum leak by using the smoke test at home. If you can’t handle it, I suggest visiting a mechanic. It will cost you around $150 – $1,000.

The Estimated Repair Cost of P0507

SolutionsCost
Fix the vacuum leakDIY: $10 – $200
Repair shop: $150 – $1,000
Clean or replace the IAC valveDIY: $70 - $400
Repair shop: $120 - $600
Clean the throttle body/ETC actuatorDIY: $200 - $500
Repair shop: $250 - $700
Readjust the throttle cableDIY: a few bucks
Repair shop: $50 - $100
Replace the throttle body/ETC actuatorDIY: $200 - $500
Repair shop: $250 - $700
Replace the PCV valveDIY: $20 - $30
Repair shop: $70 - $100
Replace the PCMDIY: Not recommended
Repair shop: $1000 - $3000

Note: The data in this table was collected in June 2022. The actual price depends on many factors, such as your car’s make and year, mechanic’s rate, etc.


You Ask, I Answer

Now you know why the idle control system RPM of a car’s engine can be higher than expected. Interestingly, the symptoms are almost similar for all the causes. Consequently, it is easy to misdiagnose the issue.

Therefore, you should invest in a reliable diagnostic procedure to pinpoint the root cause of the P0507 code and avoid unnecessary expenses.

Should you have any ideas or questions about the P0507 code, please use the comment section below. I’ll answer them asap. 

See ya!