Turbo Coupe Technical Articles Turbo Coupe Literature Contact
dg1: Service Code 25: Generate Knock Manually
Steps _Locate knock sensor and prepare to rap/tap on exhaust manifold with a 4 oz. hammer
_Run Engine Running Self-Test (engine must be at operating temperature)
_Tap exhaust manifold directly above the knock sensor immediately after the dynamic response code is given
Result Is service Code 25 present?
Direction YES

GO to Continue


Knock system OK. Rerun Engine Running Self-Test and Service any other codes from that test

Notes It is not necessary to "goose" the throttle. Ignore all other codes except Code 25

KS Information:
ComponentKnock Sensor
DescriptionThe Knock Sensor is a piezoelectric accelerometer with the sensor designed to resonate at approximately the same frequency as engine knock. The sensor uses resonant frequency to mechanically amplify the vibrations. This method allows relatively large signals to be achieved without electrical amplification and with small package size. The sensor has a thin circular piezoelectric ceramic disk which is bonded to a metal diaphragm.

Electrical connections are made through a two pin integral connector.
LocationThreaded into lower intake manifold
Wire ColorsYellow with Red stripe
Black with White stripe
NotesM12 x 1.5mm-6g
5.7K Resonant Frequency