Lean Burn System Troubleshooting

The Lean Burn System is a spark advance control system introduced in 1976 by Chrysler. The Lean Burn System has eight control sensors and an electric computer used with feedback carburetors to adjust spark advance. In 1977 the system was refined, integrating electronic ignition. By 1978 the Lean Burn System was used in most Chrysler V8s, according to Allpar. The Lean Burn System provides smooth engine warmup and operation and improved engine performance, among other improvements. The Lean Burn System was historically significant as it utilized computer sensors to process information, but there are often problems associated with the Lean Burn System. They can be resolved with a simple diagnostic test.

Things You'll Need

• Engine Analyzer

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Instructions

• 1

  Purchase or rent an engine analyzer. An engine analyzer simulates engine build-up to predict how the engine operates given certain conditions. An engine analyzer can be purchased from automotive shops or online for upwards of $120, according to Google Store. Engine analyzers can be rented from automotive and car performance shops at hourly or daily rates.

• 2

  Disconnect the pickup coil. Turn on the engine analyzer in the self-sweep mode. In self-sweep mode, the engine analyzer can be used to check the magnetic pickup coil unless the car's distributor sensors depend directly on the electronic module for operation. Do not connect the analyzer to a distributor sensor without thoroughly reading the operator's manual of your vehicle for correct connection procedures, which vary among car years, makes and models.

• 3

  Connect the red and black probes of the analyzer across the pickup coil wires and crank the engine while watching the analyzer screen. The screen should alternate above and below the zero line if the pickup is good. In Chrysler V8s, the starting pickup is easily identified since its distributor connection is larger, according to TPub.