A) Version with pressure sensor
Install a pressure gauge between the ring line and fuel
filter.
Fuel pump pressure:
a) Check at engine idle speed, or
b) connect tester EFAW 228 to control unit. Place with A at
valve testing position. Turn on ignition. Operate pump button on
tester.

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If the pump pressure¹ is less or more than 2.0 ± 0.2 kp/cm²
(28 ± 2.8 psi), loosen nut (1) and adjust the pressure with screw (2).
Coution! Adjust pressure of 3.15 litre engines to 2.3 ± 0.2 kp/cm (33 ± 2.8 psi).

¹ Refer to 13 60 009, troubleshooting fuel injection system.


Siehe auch 13 60 009
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B) Version with air flow sensor
The injection pressure² is controlled evenly with vacuum to
2.5 ± 0.2 bar (35 ± 2.8 psi) by way ot the pressure regulator
depending on load conditions.
Check: Connect a pressure gauge between the cold start
valve and ring line.
Take plug off of air flow sensor and connect wire 36 with 39 in plug.
Turn on ignition.
Squeeze fue return hose slowly and let pressure increase to about
4 bar (56 psi).
If the pressure drops below 2.5 ± 0.2 bar (35.5 ± 2.8 psi) after releasing the
return hose, the pressure regulator must be replaced.

² The injection pressure will increase past permissible limitis due to lack of
sufficient return. This will cause starting difficulties. Return line is clamped or part
of filter screen in intake devise is covered.



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