Mercedes-Benz W212 boost pressure and limp mode
Why does the W212 go into limp mode because of boost pressure?
The car limits power (limp mode) when boost pressure deviates from the target. The cause can be a leak on the intake side, a cracked charge air hose, a leaking intake manifold gasket or a missing intake manifold bolt, a faulty boost pressure sensor or a vacuum hose.
What do codes P2263 and P0299 mean?
P2263 indicates a deviation in boost pressure control, such as sticking or intermittent operation. P0299 indicates that boost pressure exceeds the permitted limit. A code alone does not identify the fault, so the cause is found by measuring.
How do you check the condition of the boost pressure sensor and the vacuum hoses?
With the ignition on and the engine off, both pressure sensors should show ambient air pressure. If the readings differ consistently, the sensor or the wiring harness is faulty. After replacing vacuum hoses, check that the hoses are in the correct order.