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View Full Version : How to combat IAT swing?



SSpdDmon
May 30th, 2007, 02:54 PM
I haven't dug into the COS's yet. I'm wondering how I can go about fixing the following problem:

Fueling is dialed in well for when IAT is 70~90*F. Once it gets up into the 100's and above, it starts to lean out (even more so in the low airflow scenarios). I don't know if it's something I can fix with the Charge Temp table or not.

Anyone else tackled this problem? The last resort is to buy two NBO2 sensors and let the fuel trims take over and add fuel in. But, I think that's about where I'm at.

joecar
May 30th, 2007, 03:48 PM
COS5 has a table A0014 "IAT VE Multiplier" just for that... :)

Big Kahuna
May 30th, 2007, 06:10 PM
You also need ot have your IAT sensor in a position that truely reflects the temp of the air being ingested.
Having it in a position where heatsoak will effect it isnt desirable, nor is having it tucked away out of the airflows path.

Mine sits right in front of the intake in a position that minimizes heatosak and allows the IAT sensor to accurately measure the intake air temp and stabilize quickly should heatsoak become an issue after beign stationary for too long (traffic lights)

SSpdDmon
May 30th, 2007, 11:41 PM
Our IAT's sit right in the back of the lid about 4 inches in front of the MAF. It's directly in the path of the airflow. Don't know if there's a more optimal place to relocate it to though.

I'll have to double check. But, I believe I seem to have more of a problem with the MAF enabled vs. it being disabled.

ViolatorTA
June 10th, 2007, 03:51 AM
Bringing back for my thoughts. SSpd, on our f-bodys we have to combat the heatsoak generated from the rising heat comming from the radiator. The IAT is positioned in a rather poor spot since it is practically above the rad. If you've done the free ram air mod you know about the long thin opening just blow the airbox. Heat rises. sitting still at a light or just idleing the heat rises from the radiator through the opening and into the bottom of the airbox heating it up, ie: heatsoaking it. The small amount of air entering the engine gets pulled along the IAT giving skewed numbers. If you've done the ram air mod it makes it worse since you open everything up to the flow of the hot air from the radiator let alone firing the car after a short shutdown from hot.

I think we need a better spot to place our IAT sensor. I see IAT's above 120 at times.