1981 Triumph TR8 Automatic TransFACTORY OEM SERVICE PROCEDURE

Ignition System Check

  1. Remove coil-to-distributor high tension cable from distributor and hold 1/4" (6 mm) from engine ground. Turn ignition switch "ON". If equipped, disconnect white/blue lead at drive resistor and check for spark at gap each time connection is broken. On models without drive resistor, crank engine and check for sparks at gap. Reconnect all wires after test.
  2. If sparking results, turn off ignition switch. Using a feeler gauge, check air gap between distributor pick-up coil and timing rotor (reluctor). Adjust as necessary. If gap is correct, crank engine to see that distributor shaft rotates.
  3. If not, check distributor and drive. If shaft does rotate, replace control module (amplifier). If there was no sparking at gap in step  1, check supply voltage at white wire (or at "SW" connector of Ballast Resistor 9BR, if equipped). If less than 11 volts, check battery, wiring and ignition switch.
  4. If voltage supply was more than 11 volts, attach voltmeter positive lead to ignition coil positive terminal and negative lead to ground. Voltage should be 11 volts or more (4-8 volts on ballasted models). If voltage is zero (0) or extremely low, check ballast resistor, coil and wires.
  5. If voltage is normal or high, attach voltmeter positive lead to coil negative terminal and negative lead to ground. If voltage reads more than 2 volts, check drive resistor. Turn ignition switch "OFF" and attach ohmmeter leads to drive resistor and check for 9-11 ohms resistance. If not to specifications, replace drive resistor. If OK, check control module and distributor grounds. If OK, but engine does not perform properly, replace control module.
  6. If voltage at coil negative terminal was less than 2 volts, disconnect white/blue wire at drive resistor (if equipped). Remove coil negative lead and check voltage at coil negative terminal. If voltage is more than 9 volts, check high tension leads and substitute a new ignition coil. Replace amplifier only if problem is not corrected.
  7. If voltage in step  6, was less than 9 volts, disconnect coil negative lead and recheck voltage at coil negative terminal. If now less than 9 volts, replace coil. If more than 9 volts, replace control module (amplifier).
Factory Service Tools

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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.