Code 34: Detonation or knock sensor circuit problem. This code will revert the ECU to the conservative safety timing and fuel mappings as well as cut the boost on a TT still utilizing the stock safety boost solenoids. We find that this code is almost always triggered by broken wires and/or corrosion on this small sub harness rather than a problem with the sensor itself. Its easist to replace with the engine out of the car, but a patient and qualified individual can change it while the transmission is out or when the lower plenum and timing are belt are removed. We always recommend replacing this harness whenever possible. If your engine is still in we often just jump the plug in the EFI harness with a Knock Sensor Bypass Plug to trick the ECU into thinking everything is normal. This does elimate the saftey feature of the detonation sensor system so we recommend fixing the problem right whenever possible.
For years the bypass or relocation of a second knock sensor were the only options aside from replacing the OEM harness. But the OEM harness has it's inadequacies that almost always mean it is the culprit of problems in the knock detection system. Now we can put those problems behind us with the Z1 Upgraded Knock Sensor Sub Harness, at less than half the price of new it is superior with: larger wire, better insulation, less unshielded length, and connectors sealed 3 ways. These features are purpose integrated to ensure years of use beyond when the factory parts woud have corroded and broken down.
If your cars knock sensor terminals are corroded and past their prime elect to add an optional new OEM knock sensor for a discounted price and restore your car's knock detection system to it's original performance.
- 1990-1996 Nissan 300ZX (Z32)