AD07.61-P-4000-53BA | Cylinder shutoff valve does not open at cylinder shutoff ON, ME-SFI fault code description | Engine 113.960 from 6/00 with Code (479) Cylinder shutoff | |
Cylinder shutoff valve for right (Y80) or left cylinder bank (Y81) does not open at cylinder shutoff ON | ||
1 | Fault code ( Display on generic scan tool) | P2094 (-) |
2 | Fault storage Activation of the engine diagnosis indicator lamp (EURO3/4) or CHECK ENGINE (MIL) malfunction indicator lamp | After expiry of test duration and fault No activation |
3 | Checking frequency Monitoring time | Continuous with cylinder shutoff ON Approx. 5 s after test prerequisites are fulfilled |
4 | Fault setting conditions | Air mass too large (does not comply with 4-cylinder engine) |
5 | Check prerequisites | - Engine speed around 500 to 4500 rpm and constant - Medium, constant load (intake manifold pressure around 200 to 1000 hPa) - Cylinder shutoff enabled - No fault in hot film mass air flow sensor, crankshaft position sensor, pressure sensor (intake manifold) - No fault in cylinder shutoff valve (output stages) - No fault in oil pressure or oil level - NO "TWC-damaging" misfires - Exhaust gas recirculation diagnosis not active - Safety fuel shutoff not active - Throttle valve actuator emergency mode not active. |
6 | Check procedure | With cylinder shutoff ON, both cylinder shutoff valves are actuated and must open. The oil pressure reaches the stud bolts in the rocker arms and release the rocker arm coupling. If the intake and exhaust valves for cylinder 2 and 3 (right cylinder bank) or cylinder 5 and 8 (left cylinder bank) are still actuated despite this, the air mass drawn in by the engine is too great. A fault cylinder shutoff valve is assumed to be the cause |
7 | | An additional note on the faulty cylinder shutoff valve is possible thanks to Lambda control: At the cylinder bank with the defective cylinder shutoff valve, the actual cylinders that are shut off draw the fresh air away from the other cylinders. The mixture becomes leaner, the O2sensor voltage drops and Lambda control reacts by enriching the mixture. |