What is the part number of the IAT sensor you are using?
What is the part number of the IAT sensor you are using?
If it is a stock IAT; use stock settings. Not sure how an IAT gets off unless it is a poorly made relocation harness. My LS3 MAF houses my IAT and I had to change the resistance values for it. At every point between 30F and 105F it reads in-line with the CTS and Trans.Originally Posted by 2000Phoenix
Thanks for clarifying. It?s a not stock. It?s. Faster acting one. Part#s for it are 25036751, 25037225, 25037334. I also did have to change the resistance points to match up with the outside air temps. Just wanted to make sure that is the correct train of action. Ok so i will leave it where it is and not worry to much about the heat soak as it comes down after driving its just hot here. Iat goes from 88-130degrees after driving and sitting for an hour. I guess its just normal and the cooling systems on these cars for removing heat is not great. I will keep tuning the ve as it is now.
Last edited by 2000Phoenix; 09-26-2022 at 03:15 PM.
Again, no that is not correct.
Is this your sensor? https://pe-ltd.com/product/iat-sensor-npt/
In the description area, click "data sheet". Page 1 has part number #25036751 referenced. This is the type of specific sensor data you need. Look at the resistance chart for -40c-150c on page two. That is what you need to enter into your tune file.
If we cannot determine what sensor you have, I recommend you buy a rife sensor just for that fact that it comes with data. It is right there on the webpage. See here - https://www.motionraceworks.com/prod...-335-f-52-1208
2000Phoenix,
You do realize that the iat (intake air temperature) is to measure the air temperature as it enters the engine? And that air temperature may be warmer than the ambient air temperature?
Im aware and see people doing all kinks of stuff like adding resistors, moving it in the intake for boost applications mainly and outside of engine bay. All seem to have good working numbers. E03901 through me off saying to keep it stock but it looks like you need to update table if its not a stock iat sensor. I will try those numbers and see what it does worse case I can always switch it back if its off.
Last edited by 2000Phoenix; 09-26-2022 at 07:52 PM.
The resistor in the link looks different from mine. I will try those values and see if it makes the iat numbers better or throws them way off. It’s pretty close now. about a 1degree difference.
Last edited by 2000Phoenix; 09-26-2022 at 07:41 PM.
1 degree from what?
I’m not sure that I have seen any discussion on relocating iat sensors other than in conjunction with the maf. There are times when you do a breakout in modifications because you can get better readings than the maf location. Never seen anyone propose moving the primary iat out from under the hood. Maybe ambient air which shouldn’t be under the hood to start with.
Do a search for heat soaking or high iat readings and you will see post on it. The iat on a cool morning is reading 1 degree from the actual outside temp on start up then heat soaks after warming up. From there but comes down after I get up around 40mph close to outside temp but increase by 20-30 degrees sitting. Looks like this is normal. Fuel trims aren’t swinging any more and are coming in line now. Just wondered if there was an actual fix is all.
If you want lower IATs, drop the thermostat temp or duct cooler air from outside the engine compartment to the air intake.
Thanks for the advice I have seen some kits that they have for fbodys and corvettes. I will look into this to see if it helps as well.
Yes. The fix is to get cooler air into the motor, not to try and move the sensor to where the air is cooler. I’m familiar with heat soak, I have an lsa swapped Camaro SS.
The air will get hot under the hood while parked or at slow speed because there isn’t enough air speed for it stay cool. Once you get air speed up, it won’t have enough time to heat up as it enters the motor.
Please, please, be very careful of what you see and hear others do - unless they are powertrain engineers well versed in theromdynamics and the complex science behind internal combustion engine function, take everything with a grain of salt. You may just be jumping off a bridge behind them! Getting good results does not mean you got there in a correct or safe way that will work in all operating conditions.
That’s exactly what’s happening. Glad someone chimed in on the iat heat soak issues with these cars. I will work on routing something to the outside air to the intake.
Definitely taking with a grain of salt on what i a see and read on here. Looking advice from more experienced tuners but will listen to some one else opinion on the matter and do more research to come to my own conclusion. Thanks for putting that out there sir.
Last edited by 2000Phoenix; 09-26-2022 at 09:02 PM.
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