Volkswagen Polo Workshop Service and Repair Manuals - Best Deals Available

Checking activation

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

• ◆ Test box V.A.G 1598/22
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Diode test lamp V.A.G 1527
• ◆ Adapter set V.A.G 1594

• ◆ Current flow diagram

Check conditions

• ● → Fuse 8 must be OK.
• ● Earth connection between engine (on gearbox bell housing) and body (below battery) OK.
• ● Earth connection in plenum chamber OK.
• ● The battery voltage must be at least 11.5 V.
• ● Engine speed sender must be OK, checking Page 24-64 .

• ● Hall sender must be OK, checking
  .
• ● Fuel pump relay must be OK

Test sequence

• ‒ → Remove cover above camshaft housing -arrows-.

• ‒ → Pull 4 pin connector off ignition transformer -arrow-.

• ‒ → Pull plug -arrows- off all injectors.

• ‒ → Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 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.
       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 according to current flow diagram.
       Wire resistance: max. 1.5 ω

If the LED lights up on one or several cylinders:

• ‒ Remove wiper arms and cowl panel:

=> Electrical system; Repair group 92; windscreen wiper system; removing and installing windscreen wiper system

• ‒ → Connect test box V.A.G 1598/22 to control unit wiring harness.

• ‒ → Check wiring between test box and the injector 2 pin connectors for open circuit using current flow diagram.
       Injector 1: Contact 2+socket 73
       Injector 2: Contact 2+socket 80
       Injector 3: Contact 2+socket 58
       Injector 4: Contact 2+socket 65
       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 will be approx. 4...6 ωhigher.

If the specification is not attained:

• ‒ Renew defective injector
  Page 24-18 , item 7 .

Checking spray pattern and for leaks

Special tools, workshop equipment, test and measuring appliances and aux. items required

• ◆ V.A.G 1331 Torque wrench (5...50 Nm)
• ◆ V.A.G 1594 A Adapter set
• ◆ V.A.G 1630 Digital potentiometer
• ◆ Measuring container

Test conditions

• ● The fuel pressure must be in order, checking
  , checking fuel pressure regulator and holding pressure.

Test sequence

• ‒ → Remove cover above camshaft housing -arrows-.
• ‒ Remove air cleaner => Page 24-23 , Fig. 3 .

• ‒ → 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 to connector contacts 1+3 and set connected side to 15 kω.

• ‒ → Detach grey 3 pin connector to engine speed sender -arrow- (on right of intake manifold).
• ‒ Unclip the wiring harness for the injectors from intake manifold and thermostat housing.

• ‒ → Pull the vacuum hose off fuel pressure regulator -arrow-.
• ‒ Remove fuel rail complete with all injectors from intake manifold (fuel hoses remain connected)
  Page 24-7 , item 7 .

• ‒ → Hold a small container under the injector to be checked and pull connectors off all other injectors.
• ‒ Operate starter, using a 2nd person. Injector must spray pulsatingly.
• ‒ Repeat check with other injectors ensuring that injector to be checked is only connected.
• ‒ Switch off ignition and afterwards check injectors for leaks. No more than
       2 drops/min
  may leak from each injector.

If the fuel loss is greater:

• ‒ Switch off ignition.
• ‒ Renew defective injector
  Page 24-18 , item 7 .

Perform installation of injectors in reverse order. When doing this note the following:

• ◆ Renew O-rings on all injectors and lightly moisten with clean engine oil.
• ◆ Fit fuel rail with secured injectors onto intake manifold and tighten evenly.