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2004 Nissan Xterra overheating, losing power

1st sign of problem 3yrs ago , overheated , lost power, had to be towed. no problem again until 4 mo. ago Overheating, losing power. have replaced fuel pump, water pump, radiator, fan thermostat, alternator. FIXD is saying Knock Sensor Circuit High, input Bank 1P0328 Severity level high ? My husband doesn’t believe FIXD, yet everything his mechanics have done, hasn’t solved problem. Anyone know ?

Why? The code IS what it IS. It is just a tool to read engine codes and any code reader would give the same answer. It IS a hint that the knock sensor is getting a signal much higher than it should. Some of the causes could be:

  • Damaged knock sensor connector
  • Open or shorted to ground knock sensor circuit
  • Shorted to voltage knock sensor circuit
  • Loose knock sensor
  • Damaged knock sensor
  • Low fuel pressure
  • Wrong fuel octane
  • Circuit experiencing electrical interference
  • Mechanical engine problem
  • Overheating engine
  • Failed PCM (rare)

Notice overheating could be the cause of the code. A bad head gasket might cause the overheating which then sets the code. Overheating 4 years ago may have weakened the head gasket on bank 1 and now its failed.

Has any mechanic run a pressure check on the cooling system? Or checked for bubbles or oily residue in the overflow tank? Or run a compression or leakdown test? If they haven’t, you need to find a better mechanic.

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