IAT2 and Coolant Temps Are The Same?

[Jon_Purdy]

Hello everyone. I need your advice on how to proceed. Just had the Aeroforce Interceptor installed and am quite surprised and confused as to why the numbers I'm seeing for the IAT2 and Coolant temps. They are identical. I'm using the VMP Triple Pass Heat Exchanger and the Bosch Intercooler Pump that came with the TVS kit.

The temps rise to 190 or so then stabilize. IAT is roughly 115-120.

With the key on but the engine off I can hear the pump running. With the engine running, I look into the tank ad see why I would call mild gurgling. The shop that tuned the car said I should be seeing "violent" bubbling.

The fact that the numbers are the same tell me the pump isn't working but I can hear it!

Please help point me in the right direction because I don't believe what I'm seeing is very good for the car.

 

[DieHarder]

Water temps are fine....

What is IAT 1 vs 2? If IAT2 is 190 that's definitely too high. The CPU will start to pull timing at 130. Where is the IAT 2 sensor? My IAT 2 can run from mid-high 80's in winter (once warm) to ~130 in summer. The difference between IAT 1 & 2 is usually about 20 - 25 deg cooler. How cold or hot it runs is largely dependent on the ambient air temps and how much I have my foot in it; but I've never really seen IAT 2 run more than 130 as long as I'm moving at freeway speeds and the pump is working. In traffic is a different story as I don't have fans on my heat exchanger/rad. If I lived in an LA I'd definitely put fans on the HE.

Does the system have a bypass in it? If not, all of the fluid has to move through the tank so you should see a fair amount of flow. If I remember correctly the Bosch pump is supposed to move about 10 gpm. Possible you may have air somewhere. I'm not running a water temp sensor for the intercooler. I've always just judged whether things are working based on IAT2. If it gets too high I start looking for problems (water level, pump, hoses, fuses, etc.).

I added a bypass (see pics) that allows the majority of water flow to bypass the tank while also allowing the tank to capture any air in the system. Direction of water flow is from passenger side of the tank to the driver's side. Got the brass Y and T fittings at the local hardware store. Works great and I've had no issues with it other than initial leaking until I sealed the "Y" fitting with some urethane cement. All good now.

 

[Laga]

IAT2 on the Interceptor does not work with aftermarket superchargers. The gauge gets its info from the list of supported Ford PIDs. If the car didn’t come with an intercooler. There will be no PID.

 

[Jon_Purdy]

Thanks for the reply. That’s news to me, the Aeroforce instructions say it does. It has the Roush TVS so yes it does have an intercooler.

 

[Jon_Purdy]

Thank you the detailed reply. This car blows past 130 on its way to 190 then it pretty much stays there. Very confusing. No bypass on this setup. I have the tiny Bosch, don’t think it puts out more than 4gpm.

Water temps are fine....

What is IAT 1 vs 2? If IAT2 is 190 that's definitely too high. The CPU will start to pull timing at 130. Where is the IAT 2 sensor? My IAT 2 can run from mid-high 80's in winter (once warm) to ~130 in summer. The difference between IAT 1 & 2 is usually about 20 - 25 deg. How cold or hot it runs is largely dependent on the ambient air temps and how much I have my foot in it; but I've never really seen mine run more than 130 as long as I'm moving at freeway speeds. In traffic is a different story.

Does the system have a bypass in it? If not, all of the fluid has to move through the tank so you should see a fair amount of flow. If I remember correctly the Bosch pump moves about 10-12 gpm. Possible you may have air somewhere. I'm not running a water temp sensor for the intercooler. I've always just judged whether things are working based on IAT2. If it gets too high I start looking for problems (water level, pump, hoses, fuses, etc.).

I added a bypass (see pics) that allows the majority of water flow to bypass the tank while also allowing the tank to capture any air in the system. Direction of water flow is from passenger side of the tank to the driver's side. Got the brass Y and T fittings at the local hardware store. Works great and I've had no issues with it other than initial leaking until I sealed it with some urethane cement. All good now.

View attachment 87476 View attachment 87477 View attachment 87478

 

[Jon_Purdy]

I forgot to mention that I don’t know where the IAT2 sensor is. The IAT temp stays right around 115-120.

Thank you the detailed reply. This car blows past 130 on its way to 190 then it pretty much stays there. Very confusing. No bypass on this setup. I have the tiny Bosch, don’t think it puts out more than 4gpm.

Water temps are fine....

What is IAT 1 vs 2? If IAT2 is 190 that's definitely too high. The CPU will start to pull timing at 130. Where is the IAT 2 sensor? My IAT 2 can run from mid-high 80's in winter (once warm) to ~130 in summer. The difference between IAT 1 & 2 is usually about 20 - 25 deg. How cold or hot it runs is largely dependent on the ambient air temps and how much I have my foot in it; but I've never really seen mine run more than 130 as long as I'm moving at freeway speeds. In traffic is a different story.

Does the system have a bypass in it? If not, all of the fluid has to move through the tank so you should see a fair amount of flow. If I remember correctly the Bosch pump moves about 10-12 gpm. Possible you may have air somewhere. I'm not running a water temp sensor for the intercooler. I've always just judged whether things are working based on IAT2. If it gets too high I start looking for problems (water level, pump, hoses, fuses, etc.).

I added a bypass (see pics) that allows the majority of water flow to bypass the tank while also allowing the tank to capture any air in the system. Direction of water flow is from passenger side of the tank to the driver's side. Got the brass Y and T fittings at the local hardware store. Works great and I've had no issues with it other than initial leaking until I sealed it with some urethane cement. All good now.

View attachment 87476 View attachment 87477 View attachment 87478

 

[DieHarder]

I forgot to mention that I don’t know where the IAT2 sensor is. The IAT temp stays right around 115-120.

I've never used the IAT's reported by the car. Wasn't exactly sure at the time where to look for them so I went with a standalone gauge. I've found this VLS dual airtemp gauge to be a good product: https://eliteracefab.com/products/revel-vls-52mm-50-300-deg-f-dual-intercooler-temperature-gauge?currency=USD&variant=36956205940904&utm_medium=cpc&utm_source=google&utm_campaign=Google Shopping&gclid=EAIaIQobChMI1_rW4vSW_wIVS_7jBx2hLQ0UEAQYAyABEgLy0fD_BwE

I put one in the elbow intake to the supercharger to take ambient intake temps (IAT 1) and the other on the compressed side of the intercooler (IAT 2). That will give you true ambient & compressed air temp readings.

The intercooler pump needs to move at least 8 - 10 gpm to be effective. If you're running 3/4" lines you can only get so much water thru them. Increasing the lines to 1" or more and/or adding a higher capacity pump will help keep things cooler. You can find a good rundown of the issues involved and how to solve for many of them here: https://www.departmentofboost.com/intercooler-system-tech/#system-tech-required

The stock S197 GT500 pump is near useless. If it were me I'd upgrade to one of these for the 13, 14 GT500 and is the one I currently use. This is a decent pump IMHO. There are better pumps out there of course but spending $500 - 700+ for an electric water pump is a bit too expensive for me. Some people will but I'm not one of them.

https://www.ebay.com/itm/314475348264?_trkparms=amclksrc=ITM&aid=1110006&algo=HOMESPLICE.SIM&ao=1&asc=20200818142055&meid=a8bb5c18654241b1ad48aeae91c53a9a&pid=101111&rk=1&rkt=12&sd=155555040281&itm=314475348264&pmt=0&noa=1&pg=2349624&algv=DefaultOrganicWebV9BertRefreshRanker&brand=Ford+Performance&_trksid=p2349624.c101111.m2109

This shows the sensor I have in the intercooler manifold (brass sensor/white wire) to take compressed air temps. The non-compressed sensor (IAT1) is in the elbow (upper right corner). Also white wire.

 

[RocketcarX]

If this is actually true it means your intercooler pump is not working.

With that being said only GT500s have IAT2

 

[DieHarder]

I forgot to mention that I don’t know where the IAT2 sensor is. The IAT temp stays right around 115-120.

Where is your IAT sensor? There will be at least one in the supercharger manifold somewhere. There has to be in order to read the compressed air temp for the tune. On mine it's screwed into the supercharger manifold on the compressed side. The other two I added for the VLS gauge. Neither was necessary for system operation or tuning.

If you can take a couple of pics of the supercharger setup you have we can probably ID it. It normally is screwed into the supercharger manifold so it can read compressed temps.

Typical IAT Sensor


IAT sensor is installed approximately here in most FI systems to read compressed air temps.

 

[Jon_Purdy]

Where is your IAT sensor? There will be at least one in the supercharger manifold somewhere. There has to be in order to read the compressed air temp for the tune. On mine it's screwed into the supercharger manifold on the compressed side. The other two I added for the VLS gauge. Neither was necessary for system operation or tuning.

If you can take a couple of pics of the supercharger setup you have we can probably ID it. It normally is screwed into the supercharger manifold so it can read compressed temps.

Typical IAT Sensor
View attachment 87504

IAT sensor is installed approximately here in most FI systems to read compressed air temps.
View attachment 87505

Found it. Mine is on the drivers side of the manifold. Still don't understand why the IAT and IAT2 are showing the same temp. The little Bosch pump isn't doing enough to move the coolant that is for sure. Will upgrading to the 2013 GT500 pump make enough of a difference? The difference between IAT and IAT2 now is as much as 65 fahrenheit. Would it be worth the effort to change to distilled water and water wetter?

 

[DieHarder]

Found it. Mine is on the drivers side of the manifold. Still don't understand why the IAT and IAT2 are showing the same temp. The little Bosch pump isn't doing enough to move the coolant that is for sure. Will upgrading to the 2013 GT500 pump make enough of a difference? The difference between IAT and IAT2 now is as much as 65 fahrenheit. Would it be worth the effort to change to distilled water and water wetter?

The IAT sensor on the driver's side is for all intents and purposes IAT 2. It's the data the CPU/tune needs to control timing and a bunch of other things. What's happened is whoever added the blower to your motor repurposed the IAT sensor in the MAF (cut the wires/extended them) and installed a new IAT sensor in the manifold so the CPU can read compressed IAT's to deal with the FI needs of the motor. This is common practice for aftermarket blower setups so nothing to worry about.

That said, to determine which IAT is which on the gauge; pull the IAT connector on the manifold with the engine idling and watch both IAT's on the gauge. That should tell you which IAT the Aeroforce is reading. Once you determine that you can try to ID the other one or leave things be. As long as you know which IAT the system is reading that's all that's necessary. If the readings from the IAT in the manifold are in the 115 - 120 range that's fine.

At this point you can continue to chase the other IAT but if it were me I'd add another IAT sensor/gauge to monitor the other reading you want or get ahold of Aeroforce to ask them what your options are since the data they're pulling from is the OBDII. Unless you have a GT500 the other IAT isn't physically present; not sure about the wiring.... In my case I simply added the VLS (dual IAT) gauge in my system and called it good but it has nothing to do with controlling timing; for that I have a separate IAT sensor in my motor in exactly the same place as yours. So, in summary I'm running an IAT in my air intake (VLS) and two (2) in the supercharger manifold to monitor compressed IAT temps. Only one of which the CPU is using to control timing and other things.



Now that I've gone thru this with you I'm kinda of curious what my SCT X4 is reading for IAT's. Think I'll connect it up and take a gander to see what my OBDII says.

 

[Pentalab]

My IAT in my small roush M90 is typ 110-115 F in summer, cruising. (70-80 F outside temps). Small Bosch 4 gpm pump, and 3/4" lines. Roush HE is 19" tall x 21" wide.....and is the same roush HE as was used in the bigger TVS-2300 setups. 5 psi boost. My IAT's drop a bit with blower on. Replaced the oem upper grille with the 7 bar grille. On a 2010, the oem upper grille blocks 80% of the airflow. With the 7 bar grille installed, it also eliminates the 2 x 90 deg bends into the 'snorkel' that feeds the airbox. Now it's outside air straight into the snorkel on drivers side of grille...which is now visible. (7 bar grille results in a foglamp delete).

The 13/14 GT-500 pump is inexpensive...and is 8 gpm. Story I got was the 13/14 GT-500 pump can use the same fuse position, same wiring, and same fuse rating.

With your 4 gpm pump, and triple bypass HE, and just cruising, you should not be seeing sky high IAT's.
The bigger pump will work, provided you have the bigger HE. The IC extracts the heat...and the HE dumps the heat. Ideally you want coolant flowing through the IC fast....and slower through the HE. Problem is, it's all one loop. Bigger pumps and smallish HE's don't work too well. The coolant is in and out of the HE too quick to dump the heat...and the hotter coolant just loops back to the IC.

The bigger pump and ur triple pass HE should be a good combo. As is, something is amiss, if IAT's are sky high, just cruising.

 

[RocketcarX]

My IAT in my small roush M90 is typ 110-115 F in summer, cruising. (70-80 F outside temps). Small Bosch 4 gpm pump, and 3/4" lines. Roush HE is 19" tall x 21" wide.....and is the same roush HE as was used in the bigger TVS-2300 setups. 5 psi boost. My IAT's drop a bit with blower on. Replaced the oem upper grille with the 7 bar grille. On a 2010, the oem upper grille blocks 80% of the airflow. With the 7 bar grille installed, it also eliminates the 2 x 90 deg bends into the 'snorkel' that feeds the airbox. Now it's outside air straight into the snorkel on drivers side of grille...which is now visible. (7 bar grille results in a foglamp delete).

The 13/14 GT-500 pump is inexpensive...and is 8 gpm. Story I got was the 13/14 GT-500 pump can use the same fuse position, same wiring, and same fuse rating.

With your 4 gpm pump, and triple bypass HE, and just cruising, you should not be seeing sky high IAT's.
The bigger pump will work, provided you have the bigger HE. The IC extracts the heat...and the HE dumps the heat. Ideally you want coolant flowing through the IC fast....and slower through the HE. Problem is, it's all one loop. Bigger pumps and smallish HE's don't work too well. The coolant is in and out of the HE too quick to dump the heat...and the hotter coolant just loops back to the IC.

The bigger pump and ur triple pass HE should be a good combo. As is, something is amiss, if IAT's are sky high, just cruising.

There is no such thing as too much pump, a CWA400 would work just fine in this application if somebody wanted to put in the effort.
A larger heat exchanger will be a bigger benefit regardless of the pump.

 

[eighty6gt]

Actual IAT's post blower: I run 135 normally, 150-160 while rotting in traffic or when just restarted after sitting, and 115 at best when cruising in my TVS 1900 car with Roush M90 lower manifold, 2013 GT500 heat exchanger and pump.

She's a FIRECRACKER. I didn't see anyone discussing that the IAT normally gets taken from the MAF sensor, stock, and I moved mine to a sensor in the manifold on the driver's side. To my knowledge, there is no IAT1/2 using the stock computer. I don't know how much I trust this sensor's readings as it's always smoking hot (as is the rest of the engine.) I should do some lab style tests with the same sensor to see if it's affected by housing temp.

 

[Jon_Purdy]

My IAT in my small roush M90 is typ 110-115 F in summer, cruising. (70-80 F outside temps). Small Bosch 4 gpm pump, and 3/4" lines. Roush HE is 19" tall x 21" wide.....and is the same roush HE as was used in the bigger TVS-2300 setups. 5 psi boost. My IAT's drop a bit with blower on. Replaced the oem upper grille with the 7 bar grille. On a 2010, the oem upper grille blocks 80% of the airflow. With the 7 bar grille installed, it also eliminates the 2 x 90 deg bends into the 'snorkel' that feeds the airbox. Now it's outside air straight into the snorkel on drivers side of grille...which is now visible. (7 bar grille results in a foglamp delete).

The 13/14 GT-500 pump is inexpensive...and is 8 gpm. Story I got was the 13/14 GT-500 pump can use the same fuse position, same wiring, and same fuse rating.

With your 4 gpm pump, and triple bypass HE, and just cruising, you should not be seeing sky high IAT's.
The bigger pump will work, provided you have the bigger HE. The IC extracts the heat...and the HE dumps the heat. Ideally you want coolant flowing through the IC fast....and slower through the HE. Problem is, it's all one loop. Bigger pumps and smallish HE's don't work too well. The coolant is in and out of the HE too quick to dump the heat...and the hotter coolant just loops back to the IC.

The bigger pump and ur triple pass HE should be a good combo. As is, something is amiss, if IAT's are sky high, just cruising.

Unbeknownst to me, they (Roush) repurposed the IAT sensor in the MAF for the sensor on the drivers side of the intake manifold. So when I selected IAT in gauge it was actually showing the IAT2 temp, if that makes any sense. If I select IAT2 in the gauge, the number it shows me is the value of the previous PID selected for the cyclic scan, in my case it was coolant temp.

 

[Laga]

Now you have to increase water flow in your intercooler system. No such thing as too much flow. I have the same VMP heat exchanger that you have. I have an Interceptor to monitor engine water temperature and IAT. I also have a separate gauge to measure water temperature going through the intercooler.
On average, the IC water temperature runs 15°F over ambient temperatures, and IAT runs 30°F over ambient at 11 pounds of boost on the Edelbrock E-Force. So on a 80°F day. The water will be 95°F and the IAT will be 110°F while driving around.
I pulled up the last datalog file I did back in Nov when Lito was doing the final adjustments to the increase to 11 pounds. The temperature that day was in the mid fifties, and the IAT spiked at 134°F under WOT. The car was fully warmed up as I need to drive over 20 to get to the sticks and an open enough road to be safe.
I have a Davies-Craig EWP150 that is setup with the bypass to the de-gas tank similar to what DieHarder has. I never actually measured flow, but when I installed it. I ran the pump into a bucket and it moved A LOT of water. It’s reasonable too at $200. Here is the location of the pump. Once the wheel well liners and bottom splash shield is in place, it is completely covered.

I also have dual fans on the heat exchanger. Both the fans and pump are powered by their own circuit with a relay.