Problem engine failure Yaris 1.0 petrol

hi to all,as the title suggests I have a problem of engine failure on a Yaris 1.0 3-cylinder engines for the year 2006 a friend of mine.The error is presented first sporadically, then more and more often until they become almost fixed,I do not remember the code exactly, but all the times that I made the diagnosis it gave me errors of adjustment, lambda probes,the last time instead of "non-activity probe lambda upstream of the catalyst".From the outset, that my friend has suffered both probes first with two then use two new probes, but nothing,the car is improved in delivery but nothing,he also replaced the catalytic converter having one available in the shop (the bodyshop).The strange thing that I noticed is that the probe after the cancellation of the error, it works for about 10 15 seconds and then stop responding to the value of 0.455 V. I have not had it so it is time to delve into the thing but it seems to be a recurring problem on these cars,you have experiences about that?

but the machine that abnormality has?

Hello, I had a similar problem and it was the engine control unit, the fixed by clicking the solder on the terminal block..

Check the wiring first of the probes, and if you can post the error code

Just today I have led uma Yaris 1.0 4 cyl year 2000 with lamp on with a cod error p0171 carbrazione lean.the machine has a vacuum in accaccelerazione.

To me, it's happened before on a yaris to changed the probe and the catalyst, and the light is back then but a short time ago on a 1000, I saw the light I asked to the customer and told me that the electricians told them it was the ecu

Air Mass meter is OK?

quaoto for the meter on those car suffer from it!!

another problem not to be underestimated close to those cars is the catalyst

The catalyst, when it is not efficient in diagnosis I see that the probes operate in the same way, instead when it is perfect I have the first probe that works is the high and low the second, and more linear.