AEM iat sensor install
Discussion
Hi guys got a question, I've install a aem iat sensor in the runner of the supercharger manifold so I can get fast & accurate readings/ better data for when it comes to mapping.
I've seen the temperature reading from the ecu of what the sensor says its running at (68 degrees when I switched the engine off for 5minutes and loaded the laptop up to see) its higher than it should since i've also charge-cooled it too.
How would I re-calibrate the AEM's sensor for what ecu was set at factory for the oem sensors resistance?
would I put parellel resistors on the 2 wires in relation to what voltage it reads out with a multi-meter?
any help/suggestions would be great!!
I've seen the temperature reading from the ecu of what the sensor says its running at (68 degrees when I switched the engine off for 5minutes and loaded the laptop up to see) its higher than it should since i've also charge-cooled it too.
How would I re-calibrate the AEM's sensor for what ecu was set at factory for the oem sensors resistance?
would I put parellel resistors on the 2 wires in relation to what voltage it reads out with a multi-meter?
any help/suggestions would be great!!
Steven - no an overly big issue as they predict the temp for higher revs when mapping but also the sensor is in the wrong place for boost, originally it sits out on the intake hose as most do. The guy before me already tapped a 3/8 hole for the aem sensor and thought whip i had off install do it right time.
Stevieturbo - yes but I bought a newest version of kpro -4 thinking it would have the tables for setting the resistance right and asked the tuner, which it does not. Which was surprising since it does just about everything else, obvious not!
Althought I seen some pages on various forums about correcting the sensor with resistor in the wiring from the ecu. Just came on to see if that was the case
Stevieturbo - yes but I bought a newest version of kpro -4 thinking it would have the tables for setting the resistance right and asked the tuner, which it does not. Which was surprising since it does just about everything else, obvious not!
Althought I seen some pages on various forums about correcting the sensor with resistor in the wiring from the ecu. Just came on to see if that was the case
I can see that it makes sense to relocate the sensor, for sure the ecu needs to be looking at the temps in the manifold not at the filter but I'd stick to the oe sensor or at least one that is compatible with the ecu you are using.
These sensors are variable resistors, if you found that adding a 1k ohm resistor corrected the values at, say, 50 degrees you'd probably find it would need 2k or10k to correct it at 20 degrees - it's unlikely that the correction would be the same throughout the range.
These sensors are variable resistors, if you found that adding a 1k ohm resistor corrected the values at, say, 50 degrees you'd probably find it would need 2k or10k to correct it at 20 degrees - it's unlikely that the correction would be the same throughout the range.
Ahh right I get what your saying! it would fix the resistance/ temp reading for the ecu to see and only correct a certain range of temperature.
There is another sensor I can try GM/T1R iat (still supposed to be 7-10 degrees out on the full range) but got the Aem with the supercharger but never thought it would be as far out.
Thanks for the response anyway guys!
There is another sensor I can try GM/T1R iat (still supposed to be 7-10 degrees out on the full range) but got the Aem with the supercharger but never thought it would be as far out.
Thanks for the response anyway guys!
The only reason not to use an OEM air temp sensor in a manifold is because it of the "open bulb" type, which when subjected to the highly pulsating pressure waves in an intake manifold and engine born vibrations can fail (the end falls off!)
ie
OPEN bulb (fast response but fragile):
Closed bulb (slow(er) response but tough:
The response time of typical closed bulb IAT sensors is around 5sec (20-80% time) which is more than adequate for any engine N/A or forced induction.
http://www.bosch-motorsport.com/media/catalog_reso...
You can buy "fast response" IAT sensors, but they are all of open bulb construction (have to be to minimise the thermal mass of the sensor) and therefore not suitable for long term use on-engine.
ie
OPEN bulb (fast response but fragile):
Closed bulb (slow(er) response but tough:
The response time of typical closed bulb IAT sensors is around 5sec (20-80% time) which is more than adequate for any engine N/A or forced induction.
http://www.bosch-motorsport.com/media/catalog_reso...
You can buy "fast response" IAT sensors, but they are all of open bulb construction (have to be to minimise the thermal mass of the sensor) and therefore not suitable for long term use on-engine.
ADDED:
If you are using the std ecu, you have no idea on the analogue / digital filtering being applied to the IAT sensor input signal and also no idea on the update rate on the trims that are applied due to that input. Chances are, a "fast response" sensor is going to do nothing due to a low frequency pass filter in the ecu anyway............
If you are using the std ecu, you have no idea on the analogue / digital filtering being applied to the IAT sensor input signal and also no idea on the update rate on the trims that are applied due to that input. Chances are, a "fast response" sensor is going to do nothing due to a low frequency pass filter in the ecu anyway............
I used to use the Bosch one you pictured, the slow....read SLOWWWWWW.
Even a few seconds after say a 1/4 mile run, temperatures were still rising. I always though my charge temps were great until I fitted a fast sensor !!! LOL It was just because the old sensor was so bloody slow temps displayed were never even close to accurate.
IMO absolutely useless for monitoring temps anywhere but holding steady state loads on a dyno.
Even a few seconds after say a 1/4 mile run, temperatures were still rising. I always though my charge temps were great until I fitted a fast sensor !!! LOL It was just because the old sensor was so bloody slow temps displayed were never even close to accurate.
IMO absolutely useless for monitoring temps anywhere but holding steady state loads on a dyno.
stevieturbo said:
I used to use the Bosch one you pictured, the slow....read SLOWWWWWW.
Even a few seconds after say a 1/4 mile run, temperatures were still rising. I always though my charge temps were great until I fitted a fast sensor !!! LOL It was just because the old sensor was so bloody slow temps displayed were never even close to accurate.
IMO absolutely useless for monitoring temps anywhere but holding steady state loads on a dyno.
er, the IAT will be rising AFTER an 1/4!!Even a few seconds after say a 1/4 mile run, temperatures were still rising. I always though my charge temps were great until I fitted a fast sensor !!! LOL It was just because the old sensor was so bloody slow temps displayed were never even close to accurate.
IMO absolutely useless for monitoring temps anywhere but holding steady state loads on a dyno.
The engine metal temps increase dramatically, and when the airflow falls back after the run, the slower air has more time to pick up this heat, and so increases in temp......
It's (practically)IMPOSSIBLE to measure true, real time temperature of anything. As long as your mapping is right, the TRUE temp is irrelevant.......
Max_Torque said:
er, the IAT will be rising AFTER an 1/4!!
The engine metal temps increase dramatically, and when the airflow falls back after the run, the slower air has more time to pick up this heat, and so increases in temp......
It's (practically)IMPOSSIBLE to measure true, real time temperature of anything. As long as your mapping is right, the TRUE temp is irrelevant.......
Not when there is no boost and cool air passing the sensor again.The engine metal temps increase dramatically, and when the airflow falls back after the run, the slower air has more time to pick up this heat, and so increases in temp......
It's (practically)IMPOSSIBLE to measure true, real time temperature of anything. As long as your mapping is right, the TRUE temp is irrelevant.......
The slow sensor really was rubbish compared to a faster one, I was amazed how different they read as never realised the old one was so s
t ! lolstevieturbo said:
Max_Torque said:
er, the IAT will be rising AFTER an 1/4!!
The engine metal temps increase dramatically, and when the airflow falls back after the run, the slower air has more time to pick up this heat, and so increases in temp......
It's (practically)IMPOSSIBLE to measure true, real time temperature of anything. As long as your mapping is right, the TRUE temp is irrelevant.......
Not when there is no boost and cool air passing the sensor again.The engine metal temps increase dramatically, and when the airflow falls back after the run, the slower air has more time to pick up this heat, and so increases in temp......
It's (practically)IMPOSSIBLE to measure true, real time temperature of anything. As long as your mapping is right, the TRUE temp is irrelevant.......
The slow sensor really was rubbish compared to a faster one, I was amazed how different they read as never realised the old one was so s
t ! lolMax_Torque said:
yes. exactly when there is no boost! The lower the airflow, the more time that air has to upheat. Or are you suggesting that the intake system of your engine (dirty air duct, clean air duct, turbo, intercooler, intake manifold) is BELOW ambient temp after a 1/4 mile run?
I never said it was below ambient....nor did I say boosted charge temps were at or below ambient.But I know uncompressed air is cooler than compressed air.
Max_Torque said:
The only reason not to use an OEM air temp sensor in a manifold is because it of the "open bulb" type, which when subjected to the highly pulsating pressure waves in an intake manifold and engine born vibrations can fail (the end falls off!)
You can buy "fast response" IAT sensors, but they are all of open bulb construction (have to be to minimise the thermal mass of the sensor) and therefore not suitable for long term use on-engine.
I think that must be quite rare or even confined to a certain manufacturer. I've never seen a broken one yet, some originals are still in use some 25yrs on.You can buy "fast response" IAT sensors, but they are all of open bulb construction (have to be to minimise the thermal mass of the sensor) and therefore not suitable for long term use on-engine.
The vibration spec for open bulb sensors is WAY lower than for fully encapsulated types, as you would expect.
As to if that is an issue or not, then it depends on the vibration characteristic of your particular engine.
Over the years i've broken loads of sensors during development as engine born vibrations can be highly localised and speed / load dependent. For example, on plastic intake manifold K series, early manifolds without a particular stiffening rib in the molding, had a vibration node that was well over 100g!! The IAT, TPS and idle stepper lasted about 5min if you sat at that particular engine speed and load.......
In all my years and different projects, i've never found a real requirement for a "fast" IAT sensor, although to be fair, the one thing i haven't done a lot of is drag racing where the runs are real short! (and get shorter the better you are ;-)
And like i said originally, if you do fit a "fast" sensor, make sure your ECU is actually going to be able to use and process that faster signal.....
As to if that is an issue or not, then it depends on the vibration characteristic of your particular engine.
Over the years i've broken loads of sensors during development as engine born vibrations can be highly localised and speed / load dependent. For example, on plastic intake manifold K series, early manifolds without a particular stiffening rib in the molding, had a vibration node that was well over 100g!! The IAT, TPS and idle stepper lasted about 5min if you sat at that particular engine speed and load.......
In all my years and different projects, i've never found a real requirement for a "fast" IAT sensor, although to be fair, the one thing i haven't done a lot of is drag racing where the runs are real short! (and get shorter the better you are ;-)
And like i said originally, if you do fit a "fast" sensor, make sure your ECU is actually going to be able to use and process that faster signal.....
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