IGNITION SYSTEM
- The Engine Control Module (ECM) is equipped with On Board Diagnostics (OBD). Before repairs such as fault finding, check the Diagnostic Trouble Code (DTC) memory first.
- For the electric components to work properly, a voltage of at least 11.5 Volts is required.
- It is possible that the control module will recognize a malfunction and store a DTC during some tests. After completing all checks and repairs, check the DTC memory and erase the memory, if necessary.
- If the engine only starts briefly and then turns off again after troubleshooting, repair or checking of the components, it may be that the immobilizer is blocking the ECM. DTC memory must then be checked and if necessary, control module must be adapted.
SAFETY PRECAUTIONS
If special testing equipment is required during road test, note the following
Scheme 22
| WARNING | Improperly secured testing and measuring equipment and distraction during a road test increase the risk of an accident. The passenger airbag could pose a risk if it deploys in a collision. Operating testing equipment while driving causes it to shift position. There is an increased risk of injury due to unsecured testing equipment. Position passenger's seat as far back as possible. The following vehicle diagnosis testers may NOT be used: VAS 5051 --, VAS 5051B --. Testing and measuring instruments -1- must lay flat on the passenger's thighs and be operated by him or her, as shown in the illustration as shown in the function test manual. |
| CAUTION | Risk of destroying electronic components when disconnecting the battery. Observe measures for disconnecting battery. |
Disconnect the battery. Refer to [For transmission(s) 02E] Removal and Installation .
To reduce the risk of personal injury and/or damage to the fuel injection and ignition system, always observe the following
Scheme 23
- Do not touch or remove ignition wires when the engine is running or turning at starter speed.
- Always switch ignition off before disconnecting or reconnecting wires for the ignition system, including high voltage wiring and test leads.
- Cleaning the engine should only be performed with ignition turned off.
- If the engine is to be cranked at starting RPM without starting (for example, for a compression test), disconnect the four ignition coil connectors.
- Disconnect the connector -arrow- from the fuel injectors.
Scheme 24
- 4-Pin Harness Connector For the ignition coil
- Bolt 9 Nm
- 3-Pin Harness Connector For Camshaft Position (CMP) sensor
- Camshaft Position (CMP) Sensor CMP sensor -G40- CMP sensor 3 -G300- Removing and installing, refer to «Camshaft Position Sensor -G40- / Camshaft Position Sensor 3 -G300»(/audi/tt-rs/8j-2009-2014/remont/ignition-system/#25l-ignitionglow-plug-system-engine-codes-cepb-coupe__camshaft-position-sensor-g40-camshaft)
- O-ring Replace if damaged Coat with clean engine oil
- Bolt 20 Nm Tightening specifications affect function of Knock Sensor (KS)
- Knock Sensor Knock Sensor (KS) 1 -G61- Knock Sensor (KS) 2 -G66- The contact surfaces between the knock sensor and cylinder block must be free of corrosion, dirt and grease. Removing and installing, refer to «Knock Sensors -G61- / Knock Sensors 2 -G66»(/audi/tt-rs/8j-2009-2014/remont/ignition-system/#25l-ignitionglow-plug-system-engine-codes-cepb-coupe__knock-sensors-g61-knock-sensors)
- Spark Plug 30 Nm Removing and installing with the spark plug removal tool 3122 B.
- Ignition Coil Ignition Coil 1 with Power Output Stage -N70- Ignition Coil 2 with Power Output Stage -N127- Ignition Coil 3 with Power Output Stage -N291- Ignition Coil 4 with Power Output Stage -N292- Ignition Coil 5 with Power Output Stage -N323- Removing and installing, refer to «IGNITION COILS»(/audi/tt-rs/8j-2009-2014/remont/ignition-system/#25l-ignitionglow-plug-system-engine-codes-cepb-coupe__ignition-coils)
Scheme 25
Tighten the bolts -1- to 5 Nm.
Scheme 26
Tighten bolts -arrows- to 5 Nm.
FASTENER TIGHTENING SPECIFICATIONS
| Components | Fastener Size | Nm |
|---|---|---|
| Camshaft Position (CMP) Sensor | 9 | |
| Knock Sensor | 20 | |
| Spark Plug | 30 |
Engine Speed (RPM) Sensor -G28- Tightening Specification
Tighten the bolts -1- to 5 Nm.
Ignition Coil Connectors - Tightening Specification
Tighten bolts -arrows- to 5 Nm.
TEST DATA
| Engine Data | 2.5L / 4V Engine | |
|---|---|---|
| Idle speed (not adjustable) | ||
| Ignition timing | Not adjustable, regulated by the control module | |
| Ignition/Glow Plug System | Single coil ignition system with 5 ignition coils (output stages integrated) that are connected directly to spark plugs via the ignition cables. | |
| Spark plugs | Names | Refer to appropriate Service Information. |
| Tightening Specifications | ||
| Ignition sequence | 1-2-4-5-3 | |
IGNITION COILS
Special tools and workshop equipment required
- Ignition Coil Puller T40039
Removing
Disconnect the connector -6- from Camshaft Position (CMP) sensor 3 -G300-.
Remove the bolts -arrows-.
Release the connectors and remove them from the ignition coils -1 through 5-.
Push the T40039 onto the ignition coil with power output stage and remove the ignition coil -arrow-.
Scheme 27
Installing
Install all the ignition coils loosely into the spark plug shaft.
Align and connect the ignition coils to the connectors all at the same time.
Push the ignition coils evenly onto the spark plugs by hand (do not use a hammer).
Attach the ignition coil wiring guide to the cylinder head cover. (Scheme 26)
Knock Sensors -G61- / Knock Sensors 2 -G66
Removing
Scheme 28
Remove the turbocharger. Refer to Removal and Installation .
Remove the electrical connectors from the bracket and disconnect
Scheme 29
- For Knock Sensor (KS) 2 -G66
- For Knock Sensor (KS) 1 -G61
Note. Ignore -arrows-.
Remove the bolts -arrows- and the heat shield -1-.
Scheme 30
Remove the bolt and the knock sensor.
Scheme 31
- KS 2
- KS 1
Installing
Install in reverse order of removal. Note the following
- Tightening specification, refer to «IGNITION OVERVIEW»(/audi/tt-rs/8j-2009-2014/remont/ignition-system/#25l-ignitionglow-plug-system-engine-codes-cepb-coupe) .
Install the turbocharger. Refer to Removal and Installation .
Camshaft Position Sensor -G40- / Camshaft Position Sensor 3 -G300
Removing
Camshaft Position (CMP) Sensor -G40
Scheme 32
Disconnect the connector -2-.
Remove the bolt -1- and CMP Sensor.
Camshaft Position (CMP) Sensor 3 -G300
Scheme 33
Disconnect the connector -1-.
Remove the bolt -2- and CMP Sensor 3.
Installing
Install in reverse order of removal. Note the following
Note. Replace the O-rings.
- Tightening specification, refer to «IGNITION OVERVIEW»(/audi/tt-rs/8j-2009-2014/remont/ignition-system/#25l-ignitionglow-plug-system-engine-codes-cepb-coupe) .
Engine Speed Sensor -G28
Removing
Scheme 34
Remove the front noise insulation -1-. Refer to Underbody Trim Panels in Removal and Installation .
Free up electrical connector -2- and disconnect.
Free up electrical wiring harness -arrows-.
Remove the bolts -1- and the Engine Speed (RPM) sensor -G28-.
Installing
Install in reverse order of removal. Note the following
- Tightening specification (Scheme 25)
Note. When installing, bring all cable ties back to same positions.
Install the noise insulation. Refer to Underbody Trim Panels in Removal and Installation .
SPECIAL TOOLS
Special tools and workshop equipment required
Scheme 35
- Ignition Coil Puller T40039