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Poor Engine Performance Problems

  1. Disconnect 4-pin connector at distributor, and install a jumper wire between pins "A" and "C" of distributor connector. If problem remains, check other causes of poor engine performance.
  2. If problem disappeared, remove jumper wire and reconnect 4-pin connector. Without disconnecting 10-pin ESC connector, attach jumper wire from pin "A" to pin "K". If problem remains, proceed to step 5).
  3. If problem disappeared in step 2), remove jumper wire and disconnect sensor wire form sensor. Measure voltage from sensor terminal to ground. Minimum reading is 80 millivolts. If OK, check for engine noises other than detonation that might cause input to sensor.
  4. If resistance reading was either high or low in the previous step, disconnect wire from sensor. Measure resistance from terminal to ground, checking again for 175-375 ohms. If high or low, replace sensor. If OK, check sensor wire and shield for open circuit. If OK, repair sensor connector. If not OK, repair harness.
  5. If in step 2), the problem still existed, remove jumper wire from pins "A" and "K". With engine running, connect positive voltmeter lead to pin "F" and negative lead to pin "K" of 10-pin connector. If reading is under 11.6 volts, repair alternator charging circuit.
  6. If over 11.6 volts, check wires in ESC harness from pins "H" and "K" for open circuits or poor connections. If OK, replace ESC controller; if not, replace or repair harness.
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