SEAT Workshop Service and Repair Manuals

Checking activation Special tools and workshop equipment required t  Test box -V.A.G 1598/31- t  Hand multimeter -V.A.G 1526 A- or multimeter -V.A.G 1715- t  Diode test lamp -V.A.G 1527B- t  Adapter set -V.A.G 1594 C- t  Current flow diagram Check conditions l  Earth connection between engine (on gearbox bell housing) and body (next to battery) OK. l  Earth connection in plenum chamber OK. l  Battery voltage at least 11.5 V. l  Engine speed sender OK, checking → Chapter. l  Hall sender OK, checking → Chapter. l  Fuel pump relay must be OK. Test sequence

–  Remove cover on camshaft housing -arrows-.

–  Pull 4-pin connector off ignition transformer -arrow-.

–  Unplug the terminal connectors -arrows- from the injectors.

–  Connect diode test lamp -V.A.G 1527 B- using aux. cables from -V.A.G 1594 C- to connector contacts of cyl. 1. –  Operate the starter and check the voltage supply for no. 1 cylinder injector.    The LED must light up. –  Repeat check at the injector connectors for cyls. 2...4. –  Switch off ignition. If the LED does not light up on any cylinder:

–  Connect diode test lamp to cyl. 1 connector, contact 1 and earth. –  Operate the starter and check the voltage supply for no. 1 cylinder injector.    The LED must light up. –  Repeat check at the injector connectors for cyls. 2...4. If the LED does not light up: –  Switch off ignition. –  Check wire between 2-pin connector contact 1 and fuel pump relay -J17- for open circuit using current flow diagram.    Wire resistance: max. 1.5 Ω If the LED does not light up on one or several cylinders:

–  Connect test box -V.A.G 1598/31- to control unit wiring harness. The engine control unit remains disconnected.

–  Check wiring between test box and the 2-pin connectors for open circuit using current flow diagram.    Injector 1: Contact 2+socket 96    Injector 2: Contact 2+socket 97    Injector 3: Contact 2+socket 88    Injector 4: Contact 2+socket 89    Wire resistance: max. 1.5 Ω –  Additionally check wires for short to one another.    Specification: ∞ Ω –  Check wiring between connector contacts 1 of injectors for open circuit to one another.    Wire resistance: max. 1.5 Ω Checking resistance of injectors Test sequence

–  Check resistance of injectors individually:    Specification: 14.0...17.0 Ω (at 20 °C) When the engine is warm the resistance rises approx. 4...6 Ω If the specification is not obtained: –  Renew defective injector → Item. Check the spray pattern and leakage

Special tools and workshop equipment required

t	Adapter set -V.A.G 1594 C-

t	Digital potentiometer -V.A.G 1630-

t	Torque spanner -SAT 8010-

t	Measuring container

Test conditions l  The fuel pressure must be OK, checking → Chapter, Checking fuel pressure regulator and holding pressure. Test sequence

–  Remove cover on camshaft housing -arrows-. –  Remove air cleaner → Fig..

–  Pull 4-pin connector off ignition transformer -arrow-.

–  Pull the 4-pin connector off coolant temperature sender -G62- with coolant temperature gauge sender -G2--arrow-.

–  Connect digital potentiometer -V.A.G 1630- using aux. cables from -V.A.G 1594 C- to connector contacts 3+4 and set connected side to 15 KΩ. –  Unclip the wiring harness for the injectors from intake manifold and thermostat housing.

–  Pull vacuum hose off fuel pressure regulator -arrow-. –  Remove fuel rail complete with all injectors from intake manifold (fuel hoses remain connected) → Item.

–  Hold a small container under the injector to be checked and unplug connectors from other injectors. –  Have 2nd person operate starter. Injector must spray in pulses. –  Repeat check with other injectors ensuring that injector to be checked is only one connected. –  Then check injectors for leaks. No more than 2 drops/min may leak out. If the fuel loss is greater: –  Switch off ignition. –  Replace faulty injector → Item. Perform installation of injectors in reverse order. When doing this note the following: t  Renew O-rings on all injectors and lightly moisten with clean engine oil. t  Fit fuel rail with secured injectors onto intake manifold and tighten evenly.