CAVU

P1026

Diagnosis information - DME (DFI)

Fuel high pressure implausible

NOTE:
- Faults in the fuel high-pressure injection system are often caused by defects in the pre-delivery system (fuel low pressure).
- Therefore, if there are problems in the fuel high-pressure injection area, the predelivery circuit must be checked first.

NOTE:
- The fault type ]Upper limit value exceeded[ or ]Lower limit value not reached[ does not necessarily have any significance.

NOTE:
- It is possible to read out in the extended fault memory whether the fault entry has been caused by the value exceeding or not reaching the respective limit:
- refer to the fault memory under
-->>[F8] INFORMATION
-->>[F5] ENVIRONMENTAL CONDITIONS<
-->Environmental conditions when fault first occurred<
-->Environment 6 (last value) is the fuel high pressure when the fault occurred:
- Value < 10 bar means that the pressure was below the limit
- Value > 135 bar means that the limit was exceeded

NOTE:

CONVERSION:
- 10,000 hPa= 10 bar = 10,000 mbar
- 1,000 kPa = 10 bar = 10,000 mbar
- IMPa = 10 bar = 10,000 mbar

Diagnostic conditions
- Battery positive voltage > 9 V
- Engine start recognized > 5 sec.
- Engine temperature -10 °C ...+100 °C (14 °F ... 212 °F)
- Engine running (driving)

Fault setting conditions
- Continuous average fuel high pressure < 10 bar or
- Continuous average fuel high pressure > 135 bar

Possible fault causes
- Only if the value is below the lower limit:
- Predelivery quantity or pressure in fuel low-pressure circuit too low
- Tank (almost) (driven) empty
- refer to the fault memory under
-->>[F8] INFORMATION
-->>[F8] EXTENDED FAULT MEMORY<
-->Value >Fuel Level Input<
-->The value is then [0%]

- If the value is below or exceeds the limits:
- Quantity control valve faulty (in fuel high-pressure pump)
- Fuel high-pressure pump faulty

8x57IRS

Sorry, I often fall for it ;-)
The most elegant solution is probably to control the pump manually, but I think this requires a PIWIS or a malicious wiring....

Petza914

The fuel system has to be able to vent in order for gas to be able to leave the tank. Maybe your vent is clogged. Does the gas cap hiss from sucking air in when you loosen it if that's happening, be careful as you can collapse your fuel tank from the suction pressure.
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Rig.Stunts

Low side fuel pumps are getting hard to find. Perhaps check availability if you don't want to miss a summer of driving.

I'll be doing mine once we find the part!

groovzilla

Good idea to start and drive your car on occasion during the winter - Even if it is just pulling the car forward 5-10' if snow is a factor.
I do this with my cars and boats every winter to keep things exercised and narrows possibilty of having issues after car sits for 3-4 months