Ensure the battery is fully charged and in good condition before making tests. Check all wiring harnesses, ignition switch, ignition coil connections, spark plug cables and connectors.

CAUTION: Do not connect any 12-volt test instruments on terminal 1 or 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 off.

On Audi 4000 (with 5-cylinder engines) and 5000 models, a Gray-colored impedance transformer may be installed in place of 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 jumper wire or secured as indicated under SYSTEM SPARK CHECK .

When installing supressors, use only 1000 ohms for high tension wires and 1000-5000 ohms for spark plug connectors. Do not wash engine when it is running. Do not use battery booster longer than 1 minute nor exceed 16.5 volts with booster.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Pre-Testing Procedures

Use the Manual With the Right Hardware

When to See a Mechanic