Volkswagen Workshop Service and Repair Manuals

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Diode test lamp V.A.G 1527
• ◆ Adapter set V.A.G 1594
• ◆ Current flow diagram

Functional check

• ‒ Start engine and run at idling speed.

• ‒ → Exhaust gas recirculation valve membrane rod is pulled towards vacuum hose connector (observe membrane rod through opening -arrow-). Exhaust gas is supplied.
• ‒ Increase engine speed to above 3200 rpm. The exhaust gas recirculation is switched off when 3200 rpm is exceeded (membrane moves towards exhaust gas manifold).

If exhaust gas recirculation does not work as described:

Check exhaust gas recirculation two-way valve control as follows:

• ‒ Switch off ignition

• ‒ → Pull 2 pin connector -2- off exhaust gas recirculation two-way valve (N161 or N18) -1-.
• ‒ Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 to connector contacts.
• ‒ Start engine and run at idling speed.
       LED must light up
• ‒ Increase speed to over 3200 rpm.
       LED must go out

LED does not light up or go out as described:

• ‒ Check wiring according to current flow diagram, or renew automatic glow period control unit (J179) as necessary.

LED lights up and goes out as described:

• ‒ Check two-way valve .
• ‒ Check exhaust gas recirculation valve => Page 26-38 .