- on Home & Garden
- Published in issue 7/2003 on page 0
Lambda Probe Readout for Carburettor Tuning
A lambda probe (or oxygen sensor) can be found on the exhaust system of most cars running on unleaded fuel. Having reached its normal operating temperature (of about 600 degrees Celcius!) the lambda probe supplies an output voltage proportional to the amount of residual oxygen measured in the exhaust gas. This information is indicative of, among others, the air/fuel ratio supplied by the carburettor(s) and hence the combustion efficiency. In modern car (and motorcycle) engines, this information is used to (electronically) adjust engine parameters like ignition timing and fuel injection.
In the circuit diagram, the anodes of D1-D10 should be shown as connected to +12 V.