U3336 BMW Fault Code

Description:

Catalytic converters must be warm before they can work properly. On a cold start the PCM provides a rich mixture to keep the cold engine running.
All that extra fuel goes into the catalytic converter. But the exhaust isn't very hot, because, ah, the engine is pretty cold. GM has employed several strategies to fire up the catalytic converter quicker and reduce cold start emissions. One way is to use a secondary air pump that pumps outside air directly into the catalytic converter.

U3336 Code Symptoms :

There are currently two main types of cylinder deactivation used today, depending on the type of engine. U3336 code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Diagnosis And Repairing U3336

U3336 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 U3336 code ?

• Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
• Clogged or faulty fuel injector (s)
• Foreign matter caught in fuel filler cap

To check for an open circuit, trace along the length of the transmission control circuit, checking for breaks in the wiring. Repair any broken wiring and make sure all connectors are fully seated and locked.

Pay close attention to connectors, looking for corrosion, bent or broken pins, or moisture in the connector. Repair any connector issues even if they are not specifically part of the transmission control circuit as they may serve a function in providing power to the transmission control circuit.