1.Feb.2014
Changing Front Lower Control Arm
11.Nov.2013
10.Nov.2013
24.July.2013
14.Mar.2013
Changing Rear Anti-RollBar Bushes
13.Mar.2013
Dipped (low) Beam Bulb Replacement
25.Feb.2013
MAF Sensor Repair or Replacement
15.Feb.2013
Front Brake Disc(Rotor) Replacement
30.Jan.2013
26.Nov.2012
24.June.2012
UK Insurance Group Ratings Added
14.June.2012
Diesel Vehicle Service Sheet Added
14.June.2012
Petrol Vehicle Service Sheet Added
22.Jan.2012
23.Oct.2011
O2 Sensors
General Information
The Jaguar X Type is fitted with 4 O2 sensors one up-stream and one down-stream on each of Bank 1 and Bank 2 in line with OBDII requirements. The up-stream sensors are located on the engine side of the catalytic converter, these are the main sensors for control of the fuel air mixture. The downstream sensors located on the exit (non engine) side of the catalytic converter performs the diagnostics for the OBD system.
Bank 1 sensor 1
and
Bank 2 sensor 1,
measure the oxygen content of the exhaust gasses as they enter
the catalytic converter, the level of oxygen in the gas mixture
is directly related to the 'burn' efficiency of the engine,
it is converted to an electrical signal and fed back to the
Engine Control Unit (ECU) to alter the fuel air mixture supplied
to the engine.
Bank 1 sensor 2
and
Bank 2 sensor 2,
measure the residue oxygen
content of the exhaust gasses as they exit the catalytic converter,
this is used by the ECU to diagnose the overall effency of the
combustion process and as part of the OBDII system it's
measurement signal will be used to help identify combustion
problems within the system.
The ratio of fuel to air in the combustion chamber is identified
with the Greek letter 'lambda' hence the term 'lambda sensor'
as the name given to the O2 sensors used in vehicles. Ideal
combustion of gasoline occurs when the fuel : air ratio is
14.7:1 (fuel is 6.8% of the mass of the mixture) at this
point the lambda value of 1.0 is assumed. As the lambda value
drops the fuel:air mixture is becoming richer (less air more
fuel) and conversely as the value rises the mixture is becoming
weaker (more air to fuel).
With the engine up-to normal working temperature, check the output of the sensor wire, normally black with Zirconia sensors, you should expect an output of 0.2 – 0.8 volts fluctuating between these reading approximately 2 – 3 times per second. If the output voltage is lower than this, i.e. 0 – 0.2 volts there will be a lean running or excess oxygen problem. If the voltage is higher than this, i.e. 0.8 – 1.2 volts then there will be a rich running or excess fuel fault.