Re: Turbo MAP & MAT interaction

[Scot Sealander <Sealand@clarityconnect.com>]

Webmaster wrote:
 
> Thanks for the reply Scott.

You are welcome.


> But my basic question is still regarding the ALDL/Tech1 MAT(IAT)
> temperature reading. If I unplug the sensor's cable, the value goes to 00
> almost instantly.

That sounds right.


> If I short the sensor out, the value goes to 0xFF almost
> instantly. So, assuming my sensor is good, it looks to me that the TECH 1
> is displaying the raw A/D converter value coming from the sensor. 

Sure looks that way!


> If this is the case, should the MAT reading be varying rapidly in response to 
> boost pressure, or only very very slowly in response to falls and rises in the
> manifold metal temp ?

The temp rise will probably not follow the temp rise out of the turbo. 
There
is an intercooler in between!  The rate of rise and final temp of the
incoming
air will depend a great deal on the intercoolers ability to cool off the
turbo heated air.  If it has a lot of capacity, you will not see a lot
of
temp rise.  I must admit to having absolutely no previous knowledge of
your
car, but it sounds like a very "interesting" car.  Must be fun to drive!

How does the air temp sensor respond to weather?  Do the readings make
sense?
Does it read an elevated temp at hot starts?  How did your manual temp
experiments with the bare sensor turn out?

Scot Sealander


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