P178F BMW Fault Code

Description:

Intake Manifold Runner Control Malfunction (Stuck Open) The IMRC system is monitored for failure during continuous, key ON engine OFF or key ON engine running self-test. The test fails when the signal on the monitor pin is less than an expected calibrated range at closed throttle. IMRC monitor signal circuit shorted to BMW PWR GND or SIG RTN Damaged IMRC actuator Damaged PCM An IMRCM PID reading approximately near 1 volt at closed throttle may indicate a fault.

P178F Code Symptoms :

If your P178F check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system P178F and engine control unit are in charge of monitoring a bunch of different , and if they get a reading that's a little out of whack, up pops the check engine light.

Diagnosis And Repairing P178F

P178F OBD 2 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission.

How to fix P178F code ?

• EVAP canister or fuel tank leaks
• Faulty Variable Camshaft Timing (VCT) position solenoid
• Failures of clutch motion/travel sensors.
• Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code P178F, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code P178F on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.