Sorry, couldn't help myself. But I did not know the screens had any more than the protective function Bosch (Probst) describes for a hot wire AMM.

Actually, I never gave a thought to removing the screens for any good reason, but have run across that recommendation from the racing enthusiasts, usually in the cone filter, cold air intake conversations.

That they straighten the air passes my BS detector, but I admit ignorance of airflow I can not see nor measure in one part compared with another part of the area being sensed by the heated wire. The same ignorance is what leads folks to buy the Tornado, I suspect. But it makes even better sense for the heated film (touching a much smaller portion of that supposedly laminar flow).

Thank you for saying you did voltage comparisons. Was that on a hot wire unit? I presume Audi also uses Bosch. That test is something I can do, provided I can get a car warm and stable enough to idle with consistent AMM output to make several repetitions of the "screen delete" and confirm what you've found as it applies to the '92 240 in this thread.
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Art Benstein near Baltimore

Birds are grouchy in the morning because their bills are over dew.