Pre-Testing Procedures
Be sure battery is at full charge and in good condition before making tests. Check all wiring harnesses, ignition switch, ignition coil, spark plug cables and connectors.
CAUTION:
Do not connect any 12-volt test instruments on terminal 15 of ignition coil, as this could damage electronic components. Do not connect any condenser/suppressor or powered test light to terminal 1 of ignition coil. Connect and disconnect test instruments only when ignition is turned "OFF".
On Audi 4000 (with 5-cylinder engines) and 5000 models, a gray-colored impedance transformer is installed in place of the idle stabilizer. When adjusting ignition timing, DO NOT disconnect the plugs from the impedance transformer.
However, when trouble shooting the ignition system, by-pass this unit just as you do the idle stabilizer. To do so, disconnect plugs of impedance transformer and plug them together.
CAUTION:
Do not touch or remove high tension wires when engine is running or cranking. Disconnect ignition wires only when ignition is "OFF". Do not crank engine unless high tension wire is removed from distributor cap and is grounded by a jumper wire or secured as indicated under System Spark Test.