Variable Cam Timing Over-advanced (Bank 1) The comprehensive component monitor (CCM) monitors the VCT position for an over-advanced camshaft timing.
The test fails when the camshaft timing exceeds a maximum calibrated value or remains in an advanced position. Cam timing improperly set No oil flow to the VCT piston chamber Low oil pressure VCT solenoid valve stuck closed Camshaft advance mechanism binding (VCT unit) P94B4 DTC is a check of the VCT unit.
Gear changes are accomplished by a command from the TCM to energize the clutch actuator to release the clutch; after which various actuators inside the transmission disengage the current gear, and depending on current operating conditions, engage the next higher or lower gear ratio. All of this happens much faster than a human driver could change gears, and in most applications, gear changes are as smooth and seamless as on any fully automatic transmission.
If your vehicle failed a P94B4 test and the P94B4 Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look : Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression. Use your OBD Express DIY to look at the oxygen sensor outputs, coolant temperature, airflow, calculated engine load, and inlet air temperature.
Difficulty Level (Expert)
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Repair Time (35 Min.)
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Cost Prediction : $ 20-50 |
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P94B4 is a kind of Powertrain Trouble Code
Powertrain of a modern automobile, comprising engine (with exhaust system), transmission, drive shaft, suspension and the wheels. In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air. |
You can view according P94B4 DTC for your car model. We selected several models to see obd2 solutions click and view it.