9000 L4-1985cc 2.0L DOHC Turbo EFI (1987)
Due to the location of the filament in the inlet duct, it is liable to become soiled and so lose its sensitivity, which will affect measurement accuracy. To
obviate this and keep the filament clean, it is heated to about 1000°C.
This "burn-off" function starts 20 seconds (4 seconds for the LH 2.2) after the engine has been switched off and continues for about 1 second.
However, a condition for burn-off is that the engine has attained a temperature of 61°C and has been run at a speed above 2100 rpm.
