The Mechanic
Guest
Lambda sensor wire info: black wire = signal to the fuel ECU
grey = earth for ECU signal
white = heater if fitted
NB B#W sometimes do not use std wire colour code, therefore the above is not definitive....sorry.
Zirconia Lambda sensors generate a voltage (up to 1 volt) by the difference in the oxygen levels between the exhaust and the atmosphere. Engine running rich = less oxygen and high voltage
Engine running lean = more oxygen low voltage
The ECU looks at this voltage and decides how to adjust the mixture for correct runing, if the sensor fails and gives a low or zero voltage the ECUthinks the mixture is lean and so will richen the mixture up....high fuel consumption anyone?
Here is a smple test to perform using a hand held digital voltmeter
this confirms if the sensor is working correctly (at the time of testing). Locate the black wire, you are going to check the voltage on this wire to earth -ve.
When the engine is hot the voltage should move back and forth between 0.2vand 0.8v every second or so. Do not worry if the sensor changes voltage a little quicker but get concerned if it takes more than 3 secs., this a slow sensor and should be replaced; the ECU will be reacting with the sensor and for a bike that would be too noticeable by the rider (choppiness in the engine power flow).
A low reading would indicate a faulty sensor or a constant weak mixture caused by something else....leaking front pipe....leaking silencer (or modded can).... leaking pipe connections.... induction air leak...too freer flowing air filter.....oo err!
If the reading is low, blip the throttle to richen the mixture momentarily and the voltage should rise, if it does not go up suspect the sensor.
By the way some Autoparts suppliers can supply replacement sensors cheaper than the dealers. Check prices and part number compatibilty before parting with your hard earned cash.
Tight valve clearances along with too wide a clearance can have a profound effect upon readings so make sure plugs, valve clearances, throttle valves (bodies) and air by-pass (brass screws) are as they should be before rushing about buying parts.
WARNING: DO NOT SEND ANY VOLTAGE BACK TO THE ECU FROM YOUR VOLTMETER/MULTI-METER.....YOU WILL CAUSE DAMAGE. This will probably only occur if you try and read RESISTANCE on any of the sensor wires. The average meter works with a 9 volt battery and this little chap will send your ECU a right good kick up the pants and blow some part of its relatively delicate circuitry.
Now if you are running with the Lambda disconnected for some reason the ECU may be on the end of its fuelling map, unless you have been instrcuted to disconnect by someone like Dyno-Jet.
May the coffers of petrol station owners and fuel additive manufacturers increase due to the unenlightened ones!
grey = earth for ECU signal
white = heater if fitted
NB B#W sometimes do not use std wire colour code, therefore the above is not definitive....sorry.
Zirconia Lambda sensors generate a voltage (up to 1 volt) by the difference in the oxygen levels between the exhaust and the atmosphere. Engine running rich = less oxygen and high voltage
Engine running lean = more oxygen low voltage
The ECU looks at this voltage and decides how to adjust the mixture for correct runing, if the sensor fails and gives a low or zero voltage the ECUthinks the mixture is lean and so will richen the mixture up....high fuel consumption anyone?
Here is a smple test to perform using a hand held digital voltmeter
this confirms if the sensor is working correctly (at the time of testing). Locate the black wire, you are going to check the voltage on this wire to earth -ve.
When the engine is hot the voltage should move back and forth between 0.2vand 0.8v every second or so. Do not worry if the sensor changes voltage a little quicker but get concerned if it takes more than 3 secs., this a slow sensor and should be replaced; the ECU will be reacting with the sensor and for a bike that would be too noticeable by the rider (choppiness in the engine power flow).
A low reading would indicate a faulty sensor or a constant weak mixture caused by something else....leaking front pipe....leaking silencer (or modded can).... leaking pipe connections.... induction air leak...too freer flowing air filter.....oo err!
If the reading is low, blip the throttle to richen the mixture momentarily and the voltage should rise, if it does not go up suspect the sensor.
By the way some Autoparts suppliers can supply replacement sensors cheaper than the dealers. Check prices and part number compatibilty before parting with your hard earned cash.
Tight valve clearances along with too wide a clearance can have a profound effect upon readings so make sure plugs, valve clearances, throttle valves (bodies) and air by-pass (brass screws) are as they should be before rushing about buying parts.
WARNING: DO NOT SEND ANY VOLTAGE BACK TO THE ECU FROM YOUR VOLTMETER/MULTI-METER.....YOU WILL CAUSE DAMAGE. This will probably only occur if you try and read RESISTANCE on any of the sensor wires. The average meter works with a 9 volt battery and this little chap will send your ECU a right good kick up the pants and blow some part of its relatively delicate circuitry.
Now if you are running with the Lambda disconnected for some reason the ECU may be on the end of its fuelling map, unless you have been instrcuted to disconnect by someone like Dyno-Jet.
May the coffers of petrol station owners and fuel additive manufacturers increase due to the unenlightened ones!
