165 $6E cold idle

[Bob Wooten]

> 
> I can understand your confusion with the mat temperature. I haven't
> quite figured it all out yet either. I do know that when the sensor is
> in the air cleaner it is an IAT (intake air temp), as opposed to mat.
> The code that I have seen handles it differently.
> 
> Apparently the mat picks up heat from the surrounding manifold. How
> much is from radiated or transferred through the sensor body is a
> good question. 
	Maybe my test will tell the answer to that (see other reply to Bruce),
> I know that as the air moves through the manifold it
> picks up heat. Slow air more, faster air less.
	thought about that but not about the air picking up temp as the speed
increases.  the FireBird induction i have is all flexible tubing so there
are lots
of large bumps to hit to generator heat.  
> Then the faster air starts
> heating up due to friction. Maybe the sensor is located in a 'dead'
> area, not much air flow past it. On TPI's I think it is mounted in the
> back of the manifold.
	The super ram is the same way, back of the plenum through the bottom of
the 
plenum, though CL of the box ST the air coming in the TB goes straight back
to hit it.
 
> Additional heating is done by the throttle body coolant passage
	not connected
> along with the EGR.
	installed, though I think disabled, I have to check that.

> To see how an IAT is handled check the azty hac of mask $88. 
	this in incoming?

> This engine uses a sensor mounted in the aircleaner housing. The canister
> type as the Firebird you have.
> 
> Here is the math I did for temp change vs AFR change (well only the
> answers):
> 
> Going from 14.7:1 afr at 102F to 0F makes the afr 17.9:1
> 
> Going from 14.7:1 afr at 0F to 102F makes the afr 12.0:1
> 
> So, the change is significant.
	great mental picture.  this leads me to think that @ WO it must make 
a difference.  I am on a mission now.  stand back, real data to follow.

	Thanks to all

> I've added an IAT sensor & support code to the ecm I'm currently
> using. It will be interesting to see how it works out. I suspect that BLM
> changes will be less.
> 
> BobR.
> 
> p.s. on the $8D mask, '730, the egr is enabled by the mat temp.
> 


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