Welcome back:
Honestly, if you have to cycle the key to get it to restart, my first suspect is fuel pressure. Have you changed the filter recently? It may be partially plugged.
Interestingly, I am only showing a 2.0L turbo diesel. Anyway, I am going to provide the directions specific to checking fuel pressure for the 2.0. It should be similar in design. The attached pictures correlate with these directions.
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COMPONENT TESTS AND GENERAL DIAGNOSTICS
Tandem Pump, Checking
Special tools, testers and auxiliary items required
picture 1
- Pressure gauge VAS 5187
picture 2
- Torque wrench (5 to 50 Nm) V.A.G 1331
- Vehicle diagnostic, testing, and information system VAS 5051
- Diagnostic cable VAS 5051/6A
Conditions
- Coolant temperature must be at least 85 degrees C.
- Pump-Injector units O.K.
- Fuel filter and fuel lines must not be plugged.
- Fuel level sensor must be OK.
Work sequence
- Loosen charge air tube and set aside.
Picture 3
- Remove locking bolt - arrow -.
Picture 4
- Install pressure gauge VAS 5187 as shown.
- Secure charge air tube in place again.
- Start engine and run at idle speed.
- Connect vehicle diagnostic, testing, and information system VAS 5051 and select operating mode "Vehicle self-diagnosis".
- Press button "01 - Engine electronics" on display.
- Press diagnostic function"08 - Read measured value block".
- Using number keypad, enter display group "1" and acknowledge entry with Q-key.
- Read idle RPM in display field "1".
- Increase engine speed to 4000 RPM.
- Observe displayed pressure on pressure gauge.
Specification: min. 7.5 bar
- Return engine to idle speed.
If the specification is not obtained:
- Clamp return line closed between fuel filter and tandem pump with a hose clamp.
- Increase engine speed to 4000 RPM.
- Observe displayed pressure on pressure gauge.
Specification: min. 7.5 bar
- Return engine to idle speed.
If the specification is now obtained:
- Pressure loss at Pump-Injector unit.
- Replace O-rings of Pump-Injector unit.
If the specification is not obtained:
- Replace tandem pump Tandem pump, removing and installing.
NOTE: After removing the pressure gauge, fasten the locking bolt to 25 Nm. Always replace the seal.
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This is where I would start. Make sure the fuel filter is clean.
Let me know what you find or if this helps.
Take care,
Joe
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Saturday, February 16th, 2019 AT 8:01 PM