IAT and P3 Gauge

**roger v** · 04-26-2014 09:43 AM

Does anyone else with the P3 gauge not get a reading for their IAT? Mine reads as zero. Figured I'd see if anyone else had this issue and give support a call on Monday.

**Skywagon** · 04-26-2014 09:53 AM

Have a P3, but don't know what IAT is? Indicated Air Temp? Or OAT, outside air temp? If it's OAT mine is working.

**jl87** · 04-26-2014 10:06 AM

Make sure it's configured for the 3.0 so it's looking for the correct sensors. I think it defaults to tsi and should be set to 3.0t or Car.3 depending on your software version.

http://www.p3cars.com/vag-install

**Jones2012s4** · 04-26-2014 05:20 PM

It reads a useless air temp.

It should read the charged air temperature sensor. I am not sure what sensor it actually reads.

**drob23** · 04-26-2014 07:28 PM

Hmm I also read 0, will need to look into this, thanks for the thread OP.

**Jones2012s4** · 04-27-2014 05:17 AM

If you check the air temp of your center DIS the P3 usually reads equal to, or a couple degrees lower than that.

**Skywagon** · 04-27-2014 06:20 AM

Originally Posted by Jones2012s4

It reads a useless air temp.

It should read the charged air temperature sensor. I am not sure what sensor it actually reads.

That is a wonderful idea. However, obviously it would require installation of a sensor at the appropriate place. I wonder what the temperature limits are of the gauge?

**roger v** · 04-27-2014 09:05 AM

Originally Posted by jl87

Make sure it's configured for the 3.0 so it's looking for the correct sensors. I think it defaults to tsi and should be set to 3.0t or Car.3 depending on your software version.

http://www.p3cars.com/vag-install

This. Once I dug through the settings I switched it over to 3.0T and got a reading. It's annoying because their instructions do not reflect the new software Car 1, Car2....etc. However...

Originally Posted by Jones2012s4

It reads a useless air temp.

It should read the charged air temperature sensor. I am not sure what sensor it actually reads.

it looks like it just reads ambient air temperature which really does nothing for me. Also, why doesn't this thing read oil temp?

Originally Posted by Skywagon

That is a wonderful idea. However, obviously it would require installation of a sensor at the appropriate place. I wonder what the temperature limits are of the gauge?

It can read any 5v source, so theoretically you could add a temperature/pressure sensor anywhere and it would read it in addition to the OBD2 readings it takes.

**Usa** · 04-27-2014 11:44 AM

Just gonna leave this here... lowest one since installing yesterday on 93 oct

**F16HTON** · 04-27-2014 12:38 PM

Originally Posted by Skywagon

That is a wonderful idea. However, obviously it would require installation of a sensor at the appropriate place. I wonder what the temperature limits are of the gauge?

There is no specific temperature limit of the gauge, however it has a digital resolution of 0-9999 (which you could choose *F or *C. The analog input for the P3 is 0-5V.

I believe that with the P3 VIDI, the air temperature that is shown, is the outside ambient air temperature (feel free to correct me if I am wrong).

The 3.0T has two air charge temperature sensors and they are located on the intake manifold runner flaps below the supercharger. A air charge temperature sensor is typically a thermocoupler and varies resistance based upon the temperature.

If you want to use the analog input on the VIDI, I feel this is the best product to use:

http://www.plxdevices.com/product_info.php?id=SEMOSMAIT

There could also be the possibility that we could ask P3 cars to modify the software on the VIDI and request the values from the 3.0T charge temperature sensors.

**Skywagon** · 04-27-2014 01:32 PM

Originally Posted by 500HPS5

There is no specific temperature limit of the gauge, however it has a digital resolution of 0-9999 (which you could choose *F or *C. The analog input for the P3 is 0-5V.

I believe that with the P3 VIDI, the air temperature that is shown, is the outside ambient air temperature (feel free to correct me if I am wrong).

The 3.0T has two air charge temperature sensors and they are located on the intake manifold runner flaps below the supercharger. A air charge temperature sensor is typically a thermocoupler and varies resistance based upon the temperature.

If you want to use the analog input on the VIDI, I feel this is the best product to use:

http://www.plxdevices.com/product_info.php?id=SEMOSMAIT

There could also be the possibility that we could ask P3 cars to modify the software on the VIDI and request the values from the 3.0T charge temperature sensors.

The air temp being read is in fact outside air temp, at least on my P3. Please forgive my ignorance, what is VIDI. I'll e-mail P3 tomorrow and ask them what they think. I'd suspect the easiest would be a digital read out on the P3 with the appropriate sensor, which you may have correctly mentioned. I sure don't know!

**F16HTON** · 04-27-2014 02:52 PM

VIDI is the name of the P3 product. Vent Integraded Digital Interface.

What I have presented to you is correct, it is the most affordable solution (sans P3 adjusting their software for the VIDI) to acquiring a reading using a intake air charge temperature sensor.

All of this can be accomplished with a VCDS though. Observing the manifold air intake temps is not something that needs to take place on a regular basis. You do not really have control over the temps, you just need to rely on the coolant system to perform as it was designed. The OEM setup was designed to support about 350# of torque on a regular basis in most environments, APRs CPS can support well over 450# of torque.

**tba** · 04-27-2014 04:57 PM

In theory, since the P3 uses the OBD2 port to pull the info, it should have access to anything you can log using VAG-COM. Charge air temp, oil temp, trans temp, actual boost should all be readable.
What would be great is if GIAC or APR would write code to use the DIS to display these things. Like the STE PPD (http://getste.com/).

**Skywagon** · 04-28-2014 07:40 AM

I sent a message to Tim at P3, cut and paste 500HP's idea. Asked Tim for his opion.

**Skywagon** · 05-04-2014 08:01 AM

I read my instructions for my P3 gauge yesterday. Allegedly the temperature that is being read is the supercharger inlet temp that is being read by the ECU?

**F16HTON** · 05-04-2014 08:37 AM

Originally Posted by Skywagon

I read my instructions for my P3 gauge yesterday. Allegedly the temperature that is being read is the supercharger inlet temp that is being read by the ECU?

AKA ambient air temp

**Skywagon** · 05-04-2014 08:58 AM

Originally Posted by 500HPS5

AKA ambient air temp

Understand, curious as to exactly where the sensor is located. I've received nothing back from P3.

**Jones2012s4** · 05-04-2014 10:25 AM

I have contacted P3 asking them to put in an update to read charged air temp.

**Jones2012s4** · 05-04-2014 10:34 AM

It is sensor G42 in this picture. Upstream of the charger. It is useless for what we are concerned with.

We would be much better off having the reading from G72 or G430 shown here.

**roger v** · 05-04-2014 10:42 AM

Originally Posted by Jones2012s4

It is sensor G42 in this picture. Upstream of the charger. It is useless for what we are concerned with.

We would be much better off having the reading from G72 or G430 shown here.

I wouldn't imagine this would be a difficult update would it? Oil temperature would be nice too so you don't have to have the laptimer up.

**F16HTON** · 05-04-2014 11:15 AM

You do realize with the P3 you can only look at one variable at a time, and to be perfectly blunt, you have zero control of the output regardless.

IAT would be fun to look at, although it really serves no purpose other than giving you "peace of mind". The only real variable the P3 offers that you as a driver have actual input with is the 0-60 timer.

**drob23** · 05-04-2014 11:22 AM

Originally Posted by roger v

I wouldn't imagine this would be a difficult update would it? Oil temperature would be nice too so you don't have to have the laptimer up.

Agreed, I thought the P3 came with oil temps. Half of the measurements are pretty useless, I don't care about EGT or speed.

Originally Posted by 500HPS5

You do realize with the P3 you can only look at one variable at a time, and to be perfectly blunt, you have zero control of the output regardless.

IAT would be fun to look at, although it really serves no purpose other than giving you "peace of mind". The only real variable the P3 offers that you as a driver have actual input with is the 0-60 timer.

Jeff has his meth setup pre-blower, so I'm sure he's very interested in that measurement, since he can change the spray parameters to adjust cooling.

Other angle: wouldn't it be nice to know how your intercooler is doing? Might tell you whether you are heat soaked? One issue I'm curious about is whether I need a CPS while running an APR stg 2 93 map at the track with 93 pump gas. I'm sure it would be smart to get the CPS, but is it needed to be safe and not pull timing etc.

**F16HTON** · 05-04-2014 01:17 PM

You only need to look at this once, after that you can make a decision. VCDS data logging would be a more useful tool. Once APR releases mobile for Simos, ECU explorer would be an option.

**hayasa** · 05-04-2014 08:28 PM

Originally Posted by Jones2012s4

It is sensor G42 in this picture. Upstream of the charger. It is useless for what we are concerned with.

We would be much better off having the reading from G72 or G430 shown here.

Someone know if this entire PDF is posted somewhere? Would be helpful.

**Jones2012s4** · 05-06-2014 07:48 AM

Received a response from P3Cars. They are passing my request to their techs.

Hopefully they can make this change.

Oil temp would be good to.

**NWS4Guy** · 05-06-2014 09:33 AM

Originally Posted by hayasa

Someone know if this entire PDF is posted somewhere? Would be helpful.

Here ya go:

http://www.s4-mtm.com/images/925803_3.0V6TFSIengine.pdf

**roger v** · 05-06-2014 10:01 AM

Originally Posted by Jones2012s4

Received a response from P3Cars. They are passing my request to their techs.

Hopefully they can make this change.

Oil temp would be good to.

This is great news.

**huckleberryshin** · 05-06-2014 10:08 AM

Are you able to update existing P3 gauges with these changes, if it ever happens? Seems like they have been talking about oil temp for some time now...

**Ketzer7** · 05-06-2014 10:15 AM

I've looking into getting one of these, and also curious how they handle software updates for the unit. There seems to be scarce info on their site about this and wondering how it would even work? I saw some mention about swapping out a chip in the unit to facilitate an upgrade.. Anyone have an idea about this?