I finally got this 1995 CAMRY 2.2 sorted.
There is only 1 sensor in MY UK model.
It was not easy to get at as its right under the engine location,
A local garage fitted it for me £10 so it saved me grovelling under the car.
TOYOTA wanted near GB£130 for there replacement .
I purchased one from...theairflowmetercompany on EBay.
Cost was GB£38 including post costs.
The car now is running very well and yesterday I had a 200 mile motorway journey
to do and had to take care as now the legal limit for roads here were so easy to exceed like I kind of remember .
So my feeling is its been faulty in some respect for some time.
In passing the Haynes Manual states that HEATED SENSORS are NOT
fitted to the 4 cylinder 5FSE motor.
Mine is 4 cylinder and it is fitted originally with a HEATED ONE.
TOYOTAs electrical manual shows a heated one in the circuit diagram.
Again thank you for information you have passed on to me.
I am sure others welcome your input to