100 SERIES AIR FILTER LIGHT

Simple solution..
Don't put your foot down & don't engage cruise control !!

Check that the hoses to and from the air cleaner haven't got a kink or are going soft. This will cause the hose to suck in on itself under heavy acceleration (2.2l deisel hiluxes did this) and cause a restriction, loss of power and the warning light.
Do you have a snorkel fitted? Some have a dry foam filter jammed in them that most people don't know about untill they clog up.
Just a thought.
Dave

I do have a snorkel fitted I will check for the foam tonight
why do they do that

check the hoses from the switch to the top and bottom of the air barrel,make sure they are connected and not kinked.is the performance down?if it isnt maybe the switch is faulty only.food for thought. cheers Paul

Maybe they're not all the same, but my 105 (1HZ motor) has two sensor rubber lines to the air cleaner, sensing only across the air filter element, running back to a pressure switch. Therefore, if the light is coming on, it means that the air cleaner is stuffed/blocked, the sensor lines are kinked, blocked or disconnected, or there is problem with the pressure switch itself. Since the sensor measures pressure drop across the filter, blockages upstream (such as a blocked snorkel) will not cause a higher pressure drop across the element - in fact, it will do quite the opposite.
Cheers
Gerry