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Old 07-15-2009, 02:46 PM   #21
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The problem is the sensor is not reporting the real intake temperature, so MS pulls fuels. On a 70*F day, I could see +100*F intake temps after a few minutes after shutdown. It's built into the code to pull the fuel. We enable the AIT corrections so add back the fuel the MS pulls.

Furthermore, when logging, I had previously noticed my intake temps would drop once I hit boost and then rise only a few degrees. This was because while cruising the sensor stayed hot in it's previous position.

Installing the AIT outside of the engine bay is a great solution, I'm pretty much always reporting ambient temps unless I'm in boost. I still use AIT corrections, but only mildly to compensate at idle for a really hot day.
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Old 07-15-2009, 10:00 PM   #22
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Braineack, i see what you're saying regarding the ambient temps, but isn't that also technically incorrect? or are you confident that your IC is effective enough that the delta between ambient and actual IAT is negligible?

Also -- i just now understood your comment from before about using EGO correction to take care of it.. I assume you make the correction speed rather slow, so it slowly dials it in, then more or less stays at that correction level?

One more thing -- what do you think of my idea of reducing the changes in the airdenfactor file and reflashing?

-Tomaj
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Old 07-30-2009, 10:12 PM   #23
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If you're running the IAT before the compressor (thus enabling you to mount it outside the engine compartment) couldn't you just mount it in the fender well or behind the bumper or something? Does it have to be located in the intake tract to read actual charge temp, or can you get the proper correction just reading ambient temps?

Also, if you need actual charge temps, shouldn't it then go between coldside IC and throttle body, to properly reflect intercooler performance?

please enlighten this unworthy one...
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Old 07-31-2009, 12:05 PM   #24
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labrat - I'm with you, I think that if you put the IAT sensor anywhere but post-IC, you're not getting real readings. The issue is though, that apparently you sometimes don't get real readings anyway because the sensor gets heatsoaked.

FWIW i t think my sensor only gets heatsoaked when you park the car for X number of minutes and then come back and re-start.. once you drive for a few seconds the temps come back down again, so it's not really a big deal in that regard.

That said, I still think that the airdenfactor.inc is way too powerful and throws off the mixture alot..

-Tomaj
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Old 07-31-2009, 12:10 PM   #25
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Quote:
Originally Posted by labrat View Post
Also, if you need actual charge temps, shouldn't it then go between coldside IC and throttle body, to properly reflect intercooler performance?

please enlighten this unworthy one...

notice where my sensor is at:

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Old 07-31-2009, 07:58 PM   #26
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i never really got my iat corrections to work, just dealt with the crappy idle till today it finally got bad enough to stall on my a couple times on the way home in traffic so i pulled over and unplugged the iat sensor and drove perfectly the rest of the way home. i do plan to get a larger intercooler and tap it into the end tank
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Old 08-01-2009, 02:20 AM   #27
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Thank you
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