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If you clear this code and re drive the vehicle does it come back every time or is it intermittent?
You have any service history on this vehicle leading up to this current problem? How many miles are on this vehicle?
I have owned this truck from new.It has 138,000 miles. Light just came on today.Never before any problem.
This code indicates there is a crankshaft to camshaft correlation timing problem. Typically this would mean that the timing belt has jumps time by 1 tooth min. However the code also could possibly indicated open or short in the VVT sensor. The sensor monitors the camshaft spinning rate. It then calculates the crankshaft revolutions to determine whether not the camshaft is out of time with the crankshaft. If this sensor starts to fail it can cause this correlation timing code. The first thing that needs to be done is to have the camshaft or VVT I sensors inspected. The only real accurate way to inspect these is with an oscilloscope. This particular code P0018 is for the passenger side bank or bank two. This is a general overview of what's going on if you want the specific details continue to read and try not to fall sleep.
The ECM optimizes the valve timing by using the VVT (Variable Valve Timing) system to control the intake camshaft. The VVT system includes the ECM, the Oil Control Valve (OCV) and the VVT controller. The ECM sends a target duty-cycle control signal to the OCV. This control signal applied to the OCV, regulates the oil pressure supplied to the VVT controller. The VVT controller can advance or retard the intake valve camshaft. The ECM calibrates the intake valve timing by setting the intake camshaft to the most retarded angle while the engine is idling. The ECM closes the OCV to retard the cam. The ECM stores this value as the VVT learning value. When the difference between the target and actual intake valve timings is 5°CA (Crankshaft Angle) or less, the ECM stores it. If the VVT learning value matches the following conditions, the ECM determines the existence of a malfunction in the VVT system, and sets the DTC.