SEAT Workshop Service and Repair Manuals

Fuel delivery quantity: check, engine codes BSE, BSF, CCSA, CMXA l  Voltage supply OK. l  Fuel pressure controller and retaining pressure okay; check → Chapter l  Fuel filter OK. –  Remove rear seat → bodywork - interior fitting work; Rep. gr.72 . –  Loosen the floor cover below the seats and tip this to rear.

–  Remove the protection elements from fuel delivery unit (depending on the version).

–  Release retainers -arrows- at cover for sealing flange.

–  First check if the connector -arrow- has been inserted correctly; pull on the connector without pressing the locking mechanism. Malfunctions may arise when the connector has not been inserted correctly. –  Detach connector. –  Check the contact on the plug connector and the fuel supply unit for damage.

–  Connect the adapter for the DSO measuring/oscilloscope module (5 contacts) -VAS 5565-to the connector in the fuel supply unit. –  Connect the remote control -V.A.G 1348/3A- to the measurement adapter / DSO (5 pin) -VAS 5565- and to battery positive (+).   Note t  The following operation is to make the fuel pump run when the engine is stopped. t  The fuel delivery rate of the fuel pump is measured at a pressure of 4 bar. Therefore, check fuel pressure before measuring delivery rate → Chapter.   WARNING Fuel supply line is pressurised. Wear safety goggles and appropriate clothing to avoid injury and contact with skin. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.

–  Remove the return hose -1- from the fuel pressure regulator.   Note Press in safety ring to release fuel lines. –  Connect the Adapter -VAS 6550/1- to the fuel pressure regulator and place the adaptor end in a measuring container. –  Operate the remote control -V.A.G 1348/3A- for approx. 5 seconds to fill the fuel filter. –  Empty the measuring container.

–  The quantity of fuel delivered by the fuel pump is dependent upon voltage. For this purpose, connect multimetre -V.A.G 1715- to outputs -1 and 5- on adapter for measuring equipment / DSO (5 pin) -VAS 5565-. –  Operate remote control for 30 seconds and measure the voltage.

–  Compare the fuel flow measured with the specification. *) Minimum delivery rate cm3/30 s **) Voltage in fuel pump with engine off and the pump working. Readout example: During the test a voltage of 10.5 volts is measured. The minimum delivery rate is, therefore, 580 cm3/ 30 seconds. If reading does not match specification: –  Check the fuel supply pipes to the filter for possible restrictions (kinks) or blockages. If the fuel line is not damaged: –  Remove the filler cap on the fuel filler neck and repeat the inspection. If the specified delivery quantity is not reached, check the purging of the fuel tank. If reading again does not match specification: –  Check the fuel filter. To do so, proceed as follows:   WARNING Fuel supply line is pressurised. Wear safety goggles and appropriate clothing to avoid injury and contact with skin. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.

–  Separate the fuel supply hose -arrow- from the fuel filter.

–  Connect fuel supply pipe to pressure tester -VAS 6550-, using adapter -VAS 6550/1-. Guide the adapter -VAS 6550/2- into a measuring beaker. –  Make sure that the drain cock is closed and that the flow valves are open. –  Operate the remote control -V.A.G 1348/3A-. Slowly close the shut-off valve -A- until a pressure of 4 bar is indicated on the pressure gauge. From here on, do not change position of shut-off tap. –  Empty the fuel tank –  Checking delivery rate again. If the minimum delivery rate is now attained: –  Replace the fuel filter → Chapter. If the minimum delivery rate is again not attained: –  Remove the fuel delivery unit and check the strainer filter for soiling. Only when up to now no fault has been detected: –  Renew fuel delivery unit → Chapter. –  Reconnect all disconnected fuel pipes. –  Bleeding the fuel system → Chapter. If delivery quantity has been attained, but nevertheless you suspect a fuel supply system fault (e.g. intermittent failure of fuel supply system): –  Checking current consumption of fuel pump → Chapter.