VANOS seals become hard and stop controlling oil flow – symptoms include a loss of power and an engine that “sounds like a bag of nails”
Vibration from worn VANOS units can cause the bolts holding the solenoids to shear, which will allow oil to shoot out of the engine and can cause terminal damage if not shut down in time
Idle control valves clog
TSB – Deposits in the injection and induction system:
Deposits at the fuel injector’s tip – symptoms include hesitation or stumble during acceleration, loss of power, poor fuel efficiency, increased emissions, and/or CEL due to misfires
Carbon deposits at the valves or intake manifold ports – symptoms include loss of power, unstable and/or rough idle, increased emissions, and/or CEL due to misfires
Combustion Chamber Deposit Interference (CCDI) – pinging or knocking which may be mistaken for engine knock that first occurs as a cold start noise that fades as the engine reaches temperature; symptoms may also include increased emissions, poor acceleration, and engine idle speed surges
Certain Vehicles
Early vehicles: Bearing shells
MY01-03: TSB – Connecting rod bearings can overheat and cause engine failure
