6052C32U20

This is a Kistler Type 6052C high-temperature piezoelectric pressure sensor for measuring cylinder pressure in combustion engines, in the U20 version. Kistler calls U20 the heavy-duty version, with a reinforced diaphragm, and recommends it for work mainly in the knock range or at very high peak pressures. The sensor is very small and is installed front-sealed in an M5 x 0.5 bore, which makes it a common choice for cylinder heads with little room and for motorcycle and other small engines.

In the U20 version the range is 0 to 300 bar (350 bar overload) with a sensitivity of about -18 pC/bar. Kistler's patented passive acceleration compensation keeps engine vibration out of the signal. The sensor can be used with conventional fuels and with hydrogen. Kistler recommends a sensitivity value at 200 C for M5 sensors.

The 6052C has a fixed connecting cable and a KIAG M4 x 0.35 connector, and needs a charge amplifier or indicating system. Kistler supplies the mounting tools: step drill 1300A51, tap 1357A, finishing tool 1300A79 (required) and torque wrench 1300A17 set to 1.5 N m. Kistler still lists the 6052C and updated its data sheet in 2026.