Injection Control Unit - Performance Curve Memory

87porsche02

Subject:
Control Unit Memory
Model

928 S4, 944S
Group

2
Part Identifier

2470
Number

8710
July 31, 1987
For model year 1987, 944S and 928 S4 DME or EZK/LH injection control units have performance curve memory which is maintained by terminal 30 (battery voltage).

By disconnecting the battery or removing the injection control unit plug, this memory will be lost.

Therefore, each time the battery or the DME or EZK/LH injection control unit is disconnected, it is necessary to run the engine for about 10 minutes at operating temperature to re-establish the performance curve memory. During this 10- minute period, performance may be erratic.

Consequently, engine specifications such as idle speed, CO % and ignition timing can only be checked after the control unit memory has been re-established.