[Erich]

deshalb hatte ich das geschrieben. Da gab es naemlich nachher noch folgende Kommentare:

Sorry, be careful:
I have to add the following I just found out, so I copy that:

quote:

jeez....a man with such a nice automobile but little knowledge of what he's doing or what's going on there.

i've cleaned my hot-wire MAF on my e34 and on my mother's car (ford) a bunch. first rule of doing that on a vehicle that you are not 100% sure of the wire strength/composition is to use a solvent that leaves no residue unless you want trouble. the only one that does that is contact cleaner marked "no residue." the fact that he's using simple green as the first step.....well. i hope that he never has trouble with that. the IP alcohol is a good step, but i don't think that it has the mechanical cleaning action to do well at that (i guess that's what the q-tip is for). I use contact cleaner because it has the cleaning action without scrubbing anything. ill spray my MAF on the e34 down and see it start to produce "grease" streaks and grease rainbows on the sides. i've only done one can of cleaner's worth, so i need to go back to the store and finish the job off.
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Answer from BillR, owner of a BMW Repair Shop:

agree Ryan, i would never use simple green on a maf, his car has a hot film maf which is different from your hot wire maf due to the fact that the hot film maf only heats up to 167F above the ambient air temps when running and your hot wire heats up to 212F above ambient when running.. and your hot wire sensor has a burn off cycle that heats the wire up to 1000C or 1832F for one second after the engine is shut off to help keep your hot wire clean...but you still get stuff on it such as soot...The only thing i use on hot film or hot wire mass air flow sensors is throttle body spray cleaner, it leaves no residue and will dissolve dirt that the contact cleaner won't

unquote
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Also der BillR hat eine eigene Reparaturwerkstatt. Er schreibt was von speziellem Drosselklappenreiniger, aber fuer Hot film oder hot wire mass flow sensor. Da muss es also Unterschiede geben.
Meiner hat diesen hot wire sensor der sich bis auf 1000 Grad kurzzeitig erwaermt zur Selbstreinigung. Auf Johan's Seite sieht man das in einem Beitrag von Sean unter MAF.