Document: Audi A4, Engine not starting (Solution)

Author: Michaell II

Engine won't start, spark plugs are wet, cranks over like no compression, no fault codes found.

Cause:
Combustion residue in the combustion chamber keeps inlet and/or outlet valves open during the start-up process.

Solution:
1. For all model years:
Install NGK BKR6EQUPA 101 000 067 AA spark plug.
2. For vehicles up to the VINs 4BXN116771, 4DXN009440, 8DXA279411:
-Modified Thermostat No. 078 121 113 G
-Modified fuel injectors: 2.4L V6 5V No. 078 133 551 BB;
2.8 l V6 5V No. 078 133 551 BA
incorporate.
3. For all vehicles up to and including the model year 2000:
Install a modified engine control unit.
To do this, you need to determine the currently valid part number for the engine control unit and compare it with the list below.
The following new data sets apply to the following engine control units.
3B0 907 551 Q as of data version 006

3B0 907 551 AE as of data status 006
The control unit with index "AE" replaces the control unit with index "T".

3B0 907 552 L, Data status 004

3B0 907 552 P as of data status 003
The control unit with index "P" replaces the control unit with index "J".

4D0 907 551 R as of data version D05
The control unit with index "R" replaces the control unit with index "F"

4D0 907 551 AF as of data status D05
The control unit with index "AF" replaces index "AE"

4B0 907 552 C Data valid from D05

4B0 907 552 F Data from D05
_________________
Bye.

Michael