How to Determine if a 2000 Silverado Has a Bad Ignition Coilby Chris Moore
Your 2000 Chevy Silverado truck will experience major problems starting up if even one of its ignition coils is not working properly. Do not, however, automatically assume an ignition coil is the problem. Inspect and test all other components of the battery and ignition system before going to the coils. Once there, you must test each coil individually for its proper resistance to determine whether replacement is necessary.
Look over the clamps on the battery cables and make sure they are clean and tight around the terminals. It's likely that a loose or corroded clamp is causing the problem, rather than an ignition coil.
Disconnect the battery cables and connect a load tester to the battery. Using the tester as per its instructions, maintain a load on the battery for 15 minutes; if the voltage drops below 9.6 volts, the battery is bad.
Open the fuse box and inspect all of the fuses related to the ignition system. If they are all in good condition, remove the fuel pump relay to disable the fuel system before proceeding.
Disconnect a spark plug wire from its plug (after reconnecting the battery) and connect a spark tester to the plug wire's boot. Connect the tester's clip to a metal ground on the truck, such as a metal bracket or bolt.
Crank the engine with the ignition key and observe the spark tester; it may be easier to have another person crank the engine. The coil is good if the tester produces a bright blue spark.
Repeat the previous two steps for each of the ignition coils and spark plug wires.
Disconnect the spark plug wire if no spark appears and connect an ohmmeter to both ends of the wire. The wire is bad if the resistance exceeds 30,000 ohms.
Disconnect the electrical connector from the ignition coil and connect a voltmeter to the two primary terminals at the coil's electrical connector. This primary resistance must be approximately .1 ohm.
Connect the voltmeter to a primary terminal and the secondary terminal on the coil's other side to measure the secondary resistance, which should be between 5,000 and 25,000 ohms.
- If all the ignition coils pass the test but you still have ignition problems, the source is likely the a spark plug or fuel injector.
- When disconnecting or connecting any cables to/from a battery (as in Step 2), always disconnect the negative cable first and connect the positive cable first.
Items you will need
- Battery load tester
- Spark tester
- "GM Full-Size Trucks, Revised Edition: 1999 through 2002 (Chilton's Total Car Care Repair Manual)"; Jeff Kibler; 2005
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