What is this sensor?

[Miller]

What is this sensor?

Its located under the throttle body of my Ver 9 Sti.

Cheers

[holden004]

My partner said he would say it is the airflow preassure sensor to the computer.

[Eight_dollar]

flipped manifold?

blocked PCV?

and block breather open?

anyway is that an added sensor ?

if anything it looks like a manfold air temp sensor (possibly an added M.A.T sensor)

[mattapo]

yep def the air temp sensor

[Miller]

 Eight dollar said:

flipped manifold?

blocked PCV?

and block breather open?

anyway is that an added sensor ?

if anything it looks like a manfold air temp sensor (possibly an added M.A.T sensor)

Haha.. Its a work in progress at the moment.. Not running yet.

Na, sensor is standard.

So it looks like a air temp sensor?

So whats the air temp sensor in the air flow meter for? Or do they run two?

Cheers

[scottspeed]

Yes this is the ACT (air charge temperature) and yes the AAT (ambient air temp) is taken from the airflow meter. Most people seem to not pay enough attention to keeping these in place. Big performance gains and constant power readings across a wide temperature range can be found if tuners utalise good compensation tables. Also most important to keeping a cast piston late model sti engine in surviving in one piece. As the factory cost cuts on engine components, reliablity is made better by smarter electronics.

[Guest]

 scottspeed said:

Yes this is the ACT (air charge temperature) and yes the AAT (ambient air temp) is taken from the airflow meter. Most people seem to not pay enough attention to keeping these in place. Big performance gains and constant power readings across a wide temperature range can be found if tuners utalise good compensation tables. Also most important to keeping a cast piston late model sti engine in surviving in one piece. As the factory cost cuts on engine components, reliablity is made better by smarter electronics.

Can you explain whats good about the MAF located one?

[pl0x]

 evowrx said:

Can you explain whats good about the MAF located one?

+1

I thought it wouldn't matter, as the ACT would overrule?

[scottspeed]

hmmm, I'm Not going to get too much into this as I make a living tuning top level rally cars.

A good tuner should be able to see how MAF sensor will show relative ambient/outside air temps being drawn into the intake system. and the one in the manifold will show how beaten up its gotten on the way in

Simple example, one before turbo, one after turbo and cooler, which gives you a temperature drop range which allows you to enter ecu information to change ignition/fuel and boost requests.

A car with 30deg manifold temp doesnt mean much when your tuning a race engine or performance engine if you cant reference it to outside airtemp. 30 deg manifold temp with a 25deg airflow sensor reading requires a different ignition/fuel/boost compensation valve compared to if it saw 5deg airflow temp reading.

[scottspeed]

to plOx, most road cars are fine with only ACT because they are not tuned to the edge. But on a race car which may be .5deg ignition away from detonation or even 1 deg into detonation, a slight change in airbox temp can have a huge effect on the engine.

When you have the time the factory does and resources, by using both sensors they end up with a more fuel efficient car with a constant power range over a wider range of temps. Older cars would always go good on a cold day/night whereas this isnt felt so much on newer cars.

[Guest]

 scottspeed said:

hmmm, I'm Not going to get too much into this as I make a living tuning top level rally cars.

A good tuner should be able to see how MAF sensor will show relative ambient/outside air temps being drawn into the intake system. and the one in the manifold will show how beaten up its gotten on the way in

Simple example, one before turbo, one after turbo and cooler, which gives you a temperature drop range which allows you to enter ecu information to change ignition/fuel and boost requests.

A car with 30deg manifold temp doesnt mean much when your tuning a race engine or performance engine if you cant reference it to outside airtemp. 30 deg manifold temp with a 25deg airflow sensor reading requires a different ignition/fuel/boost compensation valve compared to if it saw 5deg airflow temp reading.

Thats good to know. I wasnt doubting you at all just wanted to understand it. Would these sensors work as IAT for link G4? They look a little different to the GMC ones guessing they have the same function though.

[scottspeed]

yes I think from memory the plug and play g4 should already be configured to run this sensor.

If you really want it to read quicker like the bosch hot wire type, you can carefully whittle the plastic tip down with a sharp blade to reveal more of the resistor.

[titian]

 scottspeed said:

to plOx, most road cars are fine with only ACT because they are not tuned to the edge. But on a race car which may be .5deg ignition away from detonation or even 1 deg into detonation, a slight change in airbox temp can have a huge effect on the engine.

When you have the time the factory does and resources, by using both sensors they end up with a more fuel efficient car with a constant power range over a wider range of temps. Older cars would always go good on a cold day/night whereas this isnt felt so much on newer cars.

Especially when you utilise a motec to its full abilities a Dwight?

[boon]

 evowrx said:

Would these sensors work as IAT for link G4? They look a little different to the GMC ones guessing they have the same function though.

The Link G4 Plugin manual for V7-9 says that only Spec Cs have a IAT sensor on the manifold, others need an IAT added.

That said, if the Link can see it I'm sure you could calibrate it to use it.