(234-2687) New method for measuring the diesel fuel's return quantity

/ 9-3 (9440) / 2007 / 2. Engine / 4-cylinder diesel / Fuel system / Technical data / (234-2687) New method for measuring the diesel fuel's return quantity

Cars affected

Saab 9-3 M05- with engine alternative Z19DT or Z19DTH

Saab 9-5 M06- with engine alternative Z19DTH

Background

Currently, during many repairs, all (4) injectors are being replaced even though only one is defective. To avoid replacing non-defective injectors the following fault diagnosis method must be used before replacing an injector. The method determines the return quantity in fitted status for each injector, and identifies any defective injector.

The checklist must be enclosed with replaced injectors.

In the case of customer complaint, the following procedure must be carried out.

Symptom description

Too great a return quantity could affect driving in the following ways:

- The engine is difficult to start

- The engine stops by itself

- Loss of power

- Misfiring, not firing on all cylinders

Parts required

Not affected.

To remove

1.	In order to determine the return quantity for the injectors, the following conditions must be fulfilled:

•

The engine starts.

•

There is sufficient diesel fuel in the tank.

•

The diesel fuel must fulfil the producer's quality requirements.

•

There must be no contact problems for the injectors, e.g. cable failure or reversed pins.

2.	Open the bonnet.

3.	Remove the upper engine cover and insulation.

4.	Position a receptacle underneath.

5.	Remove the fuel return hose:

•

Press the locking clips (A) in the direction of the arrow.

•

Detach the fuel return hose.

6.	Seal the fuel return hose (A) with EN-47655-40 (B).

Measuring

1.	Fit the diagnostic equipment:

•

Fit the Return flow tester EN-47655 (A) onto the injectors (B).

•

Connect the measuring cylinders to the injectors. Note The joint must snap in audibly.

2.	Measure the injectors' return quantity:

•

Start the engine.

•

Run the engine until one measuring cylinder is completely full.

•

Switch off the engine. Note The maximum permitted return quantity for each individual injector is three times as much as the lowest measured return quantity.

Example 1

Shows correct return measurement.

Measuring cylinder to injector	Contents (ml)
1	41
2	44
3	50
4	46
Maximum permitted return quantity:	41 x 3 = 123
All injectors are OK

Example 2

Shows incorrect return measurement.

Measuring cylinder to injector	Contents (ml)
1	50
2	18
3	18
4	10
Maximum permitted return quantity:	10 x 3 = 30
Injector 1 has too great a return quantity and must be replaced.

To fit

1.	Remove the diagnostic equipment for injectors EN-47655 from the injectors:

2.	Press in the lock clips and remove EN-47655-40 from the fuel return hose.

3.	Fit the fuel return hose to the injectors. Note The joint must snap in audibly.

4.	Fit the upper engine cover and insulation.

5.	Close the bonnet.

6.	Remove the receptacle.

Warranty/Time Information

In the case of customer complaint and if the car is within the warranty period , use the following information to fill out the claim:

Failed Object: 24211

Fault/Reason code: 08

Location code: 09 (US=...)

Warranty Type (US):

Repair/Action code: 08

Labour Operation (US):

Time: 0.4 hr

Checklist - injection check Z19DT and Z19DTH

Note

The checklist must be enclosed with replaced injectors.

Date:
VIN:
Distance (km/miles):
Customer complaint:
CHECK ENGINE lamp:
Diagnostic trouble codes:
Other observations:
Measurement value return flow, before replacement of injector:
	Cyl 1	Cyl 2	Cyl 3	Cyl 4
Return quantity (ml), read with return flow tester EN-47655
Injection correction of return flow, read with Tech2
Measurement value return flow, after replacement of injector:
	Cyl 1	Cyl 2	Cyl 3	Cyl 4
Return quantity (ml), read with return flow tester EN-47655
Injection correction of return flow, read with Tech2

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