P1347

P1347

Diagnosis information - Control unit DME (DFI)

Valve lift control Bank 2

Diagnostic conditions
- Driving with slight acceleration (See [Information]), at:
- Large stroke (Actual value A220 = 1) :
- Period since engine was started > 5 Minute(s)
- Engine speed 1,250 ... 2,200 1/min (Actual value A020)
- Mass air flow 300 & 600 mg/stroke (Actual value A050)

- then Driving with slight acceleration, at:
- Small stroke (Actual value A220 = 0):
- Period since engine was started > 5 Minute(s)
- Engine speed 1,250 ... 2,200 1/min (Actual value A020)
- Mass air flow 180 & 350 mg/stroke (Actual value A050)

Possible fault causes
- Engine oil pressure too high or too low
- Loose contact or corrosion on connectors or lines (Power supply Solenoid valve, hydraulic valve lift control)

Fault setting condition(s)
- Diagnosis detects via the camshafts' vibration behavior that all the valves have either not switched to the other lift or have not switched quickly enough during valve lift switchover.

INFORMATION
A trip with the aforementioned conditions can be performed as follows, for example:
- Engine at operating temperature
- Level route
- Driving in 5th gear (manual)
- Vehicle rolls at approx. 50 km/h / 31 mph (approx. 1,000 rpm)
- This is followed by uniform acceleration to 2,200 rpm, at:
- Acceleration not too high (Mass air flow < 600 mg/stroke - Actual value A050)
and
- Acceleration not too low (Large stroke - Actual value A220 = 1)