Hi, I have a 01 f150 with powerdyne supercharger, non intercooled. I have my intake air temp sensor mounted into the supercharger discharge pipe, so its sensing really hot air. When I was running at the track I found that when I unplug the intake air temp sensor, the truck would pick up 3 tenths. Running 1/8 mile with it plugged in I ran a 9.8 and when I unplugged it I ran a 9.5. So my question is, what temp is the default that the computer sends when its unplugged and will I gain any more if I relocate the sensor up front, say in front of the radiator. Also, will this cause any long term effects on the engine. Thanks.

 

You should get a tune and relocate the IAT to where it will see the actual temperature of the air going into the motor. Safest and best way to do it.

My IAT failed at one point and upon datalogging the computer was telling me that IAT was defaulting to zero. So you may have picked up some timing if yours was doing the same but it's probably not that safe for the motor.

 

Using my hand held scanner, I am able to read my IAT Sensor.
The reading is within a couple degree's of what the outside air temp is reading at the time, at start up.
For example: I threw my scanner on the other day and the outside temp was about 60 degree's. The scanner was reading about 58 degree's at the IAT Sensor.
After driving a bit, the temp went up a couple of degree's. That may be from picking up some hotter air from the engine area.
You may want to get a scanner on there and check the current position of the sensor and see what temp you are reading.
There is probably some info somewhere that will give you the parameter's
(hi/low temp) that the IAT Sensor must be within.
You might want to research what the IAT Sensor does for adjustment in the PCM.
There are plenty of techs on this sight that can probably answer these ???'s.

 

How far from the intake manifold is the IAT sensor ? I believe you want to read the air temp as accurately as possible, as close to where it enters the runners to the intake valves, as possible.

I believe you should have 2 of the IAT sensors - one in the intake box, near the air filter and one on the discharge side of the blower.

I am fairly certain my Lightning has them in those locations. Sal, Jim or Johnny could probably tell you best... I'm not sure if the dual IAT support functionality is in every PCM, or just the Lightnings ???

Keep us posted on what you find.

 

I have only 1 IAT sensor. My truck was not supercharged from factory, I added the powerdyne supercharger. The intake air temp sensor is in the correct place, the supercharger discharge tube, so its sensing the temp of the air going into the intake manifold, which is pretty hot air. I think I datalogged like 120 deg on a hot day here in FL. Oh and the truck is tuned by troyer performance, I have the handheld xcal 2. The computer must be retarding the timing a lot with the sensor picking up that hot air because when I unplug the sensor, I pick up a whole lot more power. I just want to know if its safe to do this. The engine seems to run ok, I dont really hear any pinging or anything. I only do it when running at the track, because the truck runs so much quicker. Daily driving, I leave the sensor plugged in and don't worry about it. But at the track it makes a big difference. I ran a 15.0 1/4 mile with it plugged in and a 14.6 unplugged, this is on the same night and back to back runs.

 

The IAT is doing it's job.Pulling out timing when it's reading hot air!
If you trick it to think your getting cool air,,you could blow your motor with to much timing.
It's up to you,,4 tenths quicker or a new motor.
I would at least talk to Troyer to make sure the timing wont go to high.

Phil

 

Well when I datalogged the first time I went to the dyno. Intake temps were 170deg and timing advance was about 12deg. This was with the IAT sensor plugged in. Does the timing seem low? Does anyone think it can be a bit higher and still be safe? I am going to try datalogging with the sensor unplugged and see where the timing goes.