Volkswagen New Beetle. Manual - part 1424

 

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Volkswagen New Beetle. Manual - part 1424

 

 

See Diagnostic Trouble Code (DTC) Memory, Checking And Erasing .

Checking fuel pump non-return valve 

Test conditions 

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Remote control VAG 1348/3A is still connected  

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Pressure gauge VAG 1318 is still connected  

Test sequence 

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Close pressure gauge cut-off tap (lever at right angles to throughflow direction - position -B-). 

Fig. 27: Closing Pressure Gauge Cut-Off Tap (Lever At Right Angles To Throughflow Direction - 
Position -B-)
 
Courtesy of VOLKSWAGEN OF AMERICA, INC. 

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Separate remote control at short intervals, until a pressure of approx. 3 bar has built up. 

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If pressure builds up too high, lower excess pressure by carefully opening cut-off tap.  

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Watch pressure drop on gauge. After 10 minutes pressure must not drop below 2.5 bar.  

If the pressure drops further: 

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Check line connections for leaks.  

If no wiring malfunction is detected: 

NOTE:

With this check the fuel supply line connections from the fuel delivery unit to 
the point at which the pressure gauge VAG 1318 is connected will be checked 
for leaks at the same time.

WARNING:

Danger of spray when opening the cut-off tap, hold container over 
the pressure gauge free connection.

 

2003 Volkswagen New Beetle GLS 

1998-2004 ENGINE Fuel System - New Beetle, 1.8L (APH, AWV & AWP)

  

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Fuel pump malfunctioning, replace fuel delivery unit. See FUEL DELIVERY UNIT, REMOVING 
AND INSTALLING
  

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Check DTC memory: 

See Diagnostic Trouble Code (DTC) Memory, Checking And Erasing . 

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Read readiness code:  

See Readiness Code, Displaying in ENGINE PERFORMANCE. 

If the DTC memory has been erased or the Engine Control Module separated from the permanent positive, the 
readiness code must be generated again. 

See Diagnostic Trouble Code (DTC) Memory, Checking And Erasing in ENGINE PERFORMANCE. 

ELECTRONIC POWER CONTROL (EPC) SYSTEM 

EPC SYSTEM, FUNCTION 

With the EPC system the throttle valve is not operated by a cable. There is no mechanical connection between 
accelerator and throttle valve. 

The position of the accelerator is transmitted to the Engine Control Module by two throttle position sensors 
(variable resistors together in a housing) which are connected to the accelerator pedal. 

The position of the accelerator (drivers requirement) is the main input value for the Engine Control Module. 

The throttle valve is operated over the complete revolution and load range by an electric motor (throttle valve 
positioner) in the throttle valve control part. 

The throttle valve is operated by the throttle valve positioner which is controlled by the Engine Control Module.

When the engine is not running and the ignition is switched on the Engine Control Module moves the throttle 
valve exactly as prescribed by the throttle position sensor. This means that when the accelerator is depressed 
halfway the throttle valve positioner opens the throttle valve by the same amount, the throttle is then 
approximately half open. 

When the engine is running (under load) the Engine Control Module can open or close the throttle valve 
independently of the throttle position sensor. 

This means that the throttle valve can already be completely open even though the accelerator pedal is 
depressed half way. 

This also gives vastly improved consumption and exhaust emission levels at certain load conditions. 

The torque required by the engine can be produced by the Engine Control Module by optimizing the 

 

2003 Volkswagen New Beetle GLS 

1998-2004 ENGINE Fuel System - New Beetle, 1.8L (APH, AWV & AWP)

  

combination of throttle valve cross-section and charge pressure.

It is incorrect to believe that the "EPC" is comprised of one or two components only. The EPC is a system, 
which is comprised of all components which have an influence, control or monitor the position of the throttle 
valve, e.g. the throttle position sensor, the throttle valve control module, the EPC warning lamp, the Engine 
Control Module. 

Observe safety precautions. See SAFETY PRECAUTIONS WHEN WORKING ON FUEL SUPPLY 
SYSTEM
 . 

Observe rules for cleanliness. See RULES OF CLEANLINESS . 

ELECTRONIC ENGINE POWER CONTROL (EPC) SYSTEM COMPONENTS, CHECKING 

1. Bracket  

2. Connector 

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Black, 5 pin  

3. 10 N.m  

4. Throttle Position (TP) sensors -G79- and -G185- 

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Not adjustable  

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Both sensors encompassed within one assembly  

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TP sensors -G79- and -G185- communicate driver's intentions to control module  

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To remove sensors, remove cover in footwell  

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When removing remove instrument panel and pedal cluster cover  

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Checking. See THROTTLE POSITION (TP) SENSORS -G79- AND -G185-, CHECKING  

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If replaced, adapt control module for automatic transmission using scan tool. See BASIC 
SETTING, INITIATING
 .  

5. Retainer 

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For footwell cover  

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From Model Year 2002  

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Clipped onto accelerator pedal  

6. Bracket 

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For cover in footwell  

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Through Model Year 2001  

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Clipped onto accelerator pedal 

NOTE:

The following list refers to items in Fig. 28 .

 

2003 Volkswagen New Beetle GLS 

1998-2004 ENGINE Fuel System - New Beetle, 1.8L (APH, AWV & AWP)

  

Fig. 28: Checking Components Of Electronic Engine Power Control System 
Courtesy of VOLKSWAGEN OF AMERICA, INC. 

ELECTRONIC ENGINE POWER CONTROL (EPC) WARNING LAMP IN INSTRUMENT 
CLUSTER, SIGNIFICANCE 

"EPC" is the abbreviation for Electronic Engine Power Control. 

When the ignition is switched on the Engine Control Module checks all components which are important for the 
correct functioning of the electronic engine power control. 

If malfunctions are recognized in electronic power control system when the engine is running, the Engine 
Control Module will switch on the EPC lamp (these malfunctions are marked in the DTC table). Simultaneously 
an entry is made in the Engine Control Module DTC memory. 

Location of EPC warning lamp 

Fig. 29: Locating Electronic Engine Power Control Warning Lamp 
Courtesy of VOLKSWAGEN OF AMERICA, INC.

 

2003 Volkswagen New Beetle GLS 

1998-2004 ENGINE Fuel System - New Beetle, 1.8L (APH, AWV & AWP)

  

 

 

 

 

 

 

 

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