1991 Mercedes Benz 350SDLFACTORY OEM SERVICE PROCEDURE

EZL Electronic Ignition Checks: Spark

Remove fuel pump relay or MAS unit before cranking engine. Using high output spark tester, inspect coil wire for spark and then inspect each spark plug wire. Using ohmmeter, verify correct spark plug wire resistance on suspected wires. See HIGH TENSION WIRE RESISTANCE TABLE.

HIGH TENSION WIRE RESISTANCE

Application Ohms
All Wires 25,000-30,000
Factory Service Tools

Use the Manual With the Right Hardware

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When to See a Mechanic

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

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.