P2018 Intake Manifold Impeller Position Sensor / Switch Circuit Intermittent Bank 1

OBD-II DTC Datasheet

Intake Manifold Impeller Position Sensor / Switch Circuit Malfunction Bank 1

What does this mean?

This Generic Powertrain / Engine DTC is commonly applied to fuel injection engines from most manufacturers since 2003.

These manufacturers include, but are not limited to, Ford, Dodge, Toyota, Mercedes, Volkswagen, Nissan, and Infiniti.

This code mainly deals with the value provided by the intake manifold flow control valve / sensor, also called the IMRC valve / sensor (usually located at one end of the intake manifold), which helps the vehicle PCM to monitor the amount of air. allowed in the engine at different speeds. This code is set for bank 1, which is the cylinder group that includes cylinder number 1. This could be a mechanical or electrical fault, depending on the vehicle manufacturer and the fuel system.

Troubleshooting steps may vary depending on the make, fuel system and intake manifold valve position / position sensor (IMRC) type and wire colors.

symptoms

Symptoms of a P2018 engine code may include:

Malfunction Indicator Lamp (MIL) illuminated
Lack of power
Random misfires
Poor fuel economy

reasons

Typically, the reasons for setting this code are as follows:

Stuck / malfunctioning throttle / body
Stuck / defective IMRC valve
Faulty actuator / IMRC sensor
Rare - Faulty Powertrain Control Module (PCM) (requires programming after replacement)

Diagnostic steps and repair information

A good starting point is always to check the Technical Service Bulletins (TSB) for your particular vehicle. Your problem may be a known issue with a known manufacturer-released fix and could save you time and money while troubleshooting.

The most common faulty items (and most often misdiagnosed) in these systems are: IMRC vacuum solenoids, since carbon builds up inside the ventilation section and prevents them from being ventilated properly, if at all, and secondly, IMRC plates stick / bond from - for carbon deposits around them.

First, look for other DTCs. If any of these are related to the intake / engine system, diagnose them first. A misdiagnosis is known to occur if a technician diagnoses this code before any system codes related to intake / engine performance are thoroughly diagnosed and rejected. Check for leaks at inlet or outlet. An intake leak or vacuum leak will deplete the engine. Exhaust gas leakage from the air-fuel / oxygen ratio (AFR / O2) sensor gives the impression of a lean-burn engine.

The next step in this process is to find the IMRC valve / sensor on your specific vehicle. Once detected, visually inspect the connectors and wiring. Look for scuffs, scratches, exposed wires, abrasions, or melted plastic connectors. Disconnect the connectors and take a close look at the terminals (metal parts) inside the connectors. Make sure they are not burnt or rusty. When in doubt, purchase electrical contact cleaner from any parts store if terminal cleaning is required. If this is not possible, use rubbing alcohol and a small plastic bristled brush (worn out toothbrush) to brush them. Let them air dry after cleaning. Fill the connector cavity with dielectric silicone compound (the same material they use for bulb holders and spark plug wires) and reassemble.

If you have a scan tool, clear the diagnostic trouble codes from memory and see if the code returns. If this is not the case, then there is most likely a connection problem.

If the code does return, we will need to check the IMRC valve / sensor voltage signals coming from the PCM as well. Monitor the IMRC sensor voltage on your scan tool. If no scan tool is available, check the signal from the IMRC sensor with a digital volt ohm meter (DVOM). With the sensor connected, the red wire of the voltmeter must be connected to the signal wire of the IMRC sensor and the black wire of the voltmeter must be connected to ground. Start the engine and check the IMRC sensor input. Click on the throttle. As the engine speed increases, the IMRC sensor signal should change. Check the manufacturer's specs, as there may be a table informing you of how much voltage should be at a given RPM.

If it fails this test, you will need to make sure the IMRC valve will move and not stick or get stuck in the intake manifold. Remove the IMRC sensor / actuator and grasp the pin or lever that moves the plates / valves in the intake manifold. Be aware that they may have a strong return spring attached to them, so they may experience tension when pivoting. When turning the plates / valves, check for binding / leaks. If so, you will need to replace them and this usually means that you will need to replace the entire intake manifold. It is better to entrust this task to professionals.

If the IMRC plates / valves rotate without binding or excessive loosening, this indicates the need to replace the IMRC sensor / actuator and retest.

Again, it cannot be stressed enough that all other codes must be diagnosed before this, since problems that cause other codes to be set can also cause this code to be set. It also cannot be stressed enough that after the first or two diagnostic steps have taken place and the problem is not obvious, it would be a prudent decision to consult with an automotive professional regarding repairing your vehicle, as most of the repairs from there onward require removing and replacing the intake manifold in order to correct this code and engine performance issue correctly.

Related DTC discussions

There are currently no related topics in our forums. Post a new topic on the forum now.

Need more help with your p2018 code?

If you still need help with DTC P2018, post a question in the comments below this article.

NOTE. This information is provided for informational purposes only. It is not intended to be used as a repair recommendation and we are not responsible for any action you take on any vehicle. All information on this site is protected by copyright.