[200q20v] Insulating MAF sensor body?

Reid, Les C. Les.Reid at Centrilift.com
Wed Jun 20 09:14:40 EDT 2001

I agree that its probably neglectable but our engines sure get hot over on
that side, it just got me thinking. 

Since a hot wire anemometer velocity measurement is only accurate when you
have a known inlet air temperature the question is: What inlet temperature
does the ecu use for the MAF wire, and what is the actual temperature of the
air as it passes the hot wire?  If those two values are different then some
error is introduced.

I agree that the long intake pipe probably adds a lot of heat to the air
(and thus decreases power) but that will not affect air mass measurement
since the intake air temp sensor is downstream, so no error is introduced to
the ecu because of the hotter air. 
We go to all the trouble of sending the air through a intercooler and then
down that long hot steel pipe; A insulator for the pipe is probably worth


-----Original Message-----
From: C1J1Miller at aol.com [mailto:C1J1Miller at aol.com]
Sent: Tuesday, June 19, 2001 8:14 PM
To: Les.Reid at centrilift.com; 200q20v at audifans.com
Subject: Re: [200q20v] Insulating MAF sensor body?

That's an old article, and I don't think it is accurate for our cars.  The 
MAF is plastic; and pretty well insulated from the turbo and other sources
heat.  Plus, that cool air flowing through it would keep it cool.

Insulating the pipe across the top of the valve cover might be a better 
suggestion; it tends to pick up some heat from the engine. However, I doubt 
it really transfers all that much to the air being combusted, as it is also 
warmer than ambient.

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