defender300td1 said:
Air temperature
: The current air intake temperature in degrees centigrade, derived from the air intake
temperature sensor.
I think this refers to the maf sensor that reads air intake I have not seen any reading device it the nano I know the laters cars have a maf sensor in the air intake! And that the pre maf had a sensor screwed into the air intake manifold so if your saying the air temp readings on nicks nano are not for the maf what is it for the previous sensor before maf was introduced if so what in the nano reads the maf as far as I'm concerned its the air temp as that's in the air intake and not the intake manifold
Click to expand...
As I said IAT is pre MAF, air flow & density are what matter.
I will certainly re-check and warm the engine up this time, but it is covered somewhere in the info, just have not got time to look at the moment.
 
defender300td1 said:
Have you actually had the maf off and cleaned it around the hot film with electrical cleaner to remove any oil deposits . The air temp on the nano is the maf whatever setting its at it should increase with the revs take it for a drive around and check that is rises if it doesn't its duff it should increase to a maximum of around 150 and be between 30-50 at idlel :)
Click to expand...

Saint.V8 said:
Surely you're talking intake air volume and not temperature....
Click to expand...

defender300td1 said:
Saint. The volume is going though, but how does the the maf work the hot film/ wire heats up the air passing through cools it thus air temp the more air going through volume as you put it cools it down so the hotter its got to get that's why it's under tempi not volume

Air temperature
: The current air intake temperature in degrees centigrade, derived from the air intake
temperature sensor.
Click to expand...

defender300td1 said:
But its the volume of air that the maf registers forget pre maf cars nicks Is maf the more air the cooler the the sensor the sensor has to increase its heat and that's where the readings rise don't see how you can Check it on yours data your pre egr are you not .
Click to expand...
Subject Matter: Intake Air TEMPERATURE

Your first post indicates a fluctuation based on engine speed.....

I then pointed out this is a measurement of air VOLUME

You then state how the MAF works to measure air VOLUME, but quote about air TEMPERATURE

The MAF as indicated by Datatek doesn't have an Air TEMPERATURE sensor but derives a 'theroetical' air TEMPERATURE from the mass of air entering the MAF (I could go on to explain the combined Gas Laws by Charles, Boyles and some french geezer called Gay-Lussac to determine TEMPERATURE using Density, volume (mass) and pressure but it would bore the ****e out of you...!).

I pointed out that IA TEMEPRATURE will not fluctuate wildly as you suggest it does, but you must be talking about VOLUME.....you then continued to school me on the workings of the MAF and how it derives the VOLUME of the intake air....but not how it derives intake air TEMEPRATURE which is what we were all talking about!
 
Last edited:
Saint.V8 said:
Subject Matter: Intake Air TEMPERATURE

Your first post indicates a fluctuation based on engine speed.....

I then pointed out this is a measurement of air VOLUME

You then state how the MAF works to measure air VOLUME, but quote about air TEMPERATURE

The MAF as indicated by Datatek doesn't have an Air TEMPERATURE sensor but derives a 'theroetical' air TEMPERATURE from the mass of air entering the MAF (I could go on to explain the combined Gas Laws by Charles, Boyles and some french geezer called Gay-Lussac to determine TEMPERATURE using Density and pressure but it would bore the ****e out of you...!).

I pointed out that IA TEMEPRATURE will not fluctuate wildly as you suggest it does, but you must be talking about VOLUME.....you then continued to school me on the workings of the MAF and how it derives the VOLUME of the intake air....but not how it derives intake air TEMEPRATURE which is what we were all talking about!
Click to expand...
So cut a long story short what reading in the nano it represented by the maf sensor always thought it was air temp that I though was just actualy taking a reading from the maf sensor ???
 
defender300td1 said:
So cut a long story short what reading in the nano it represented by the maf sensor always thought it was air temp that I though was just actualy taking a reading from the maf sensor ???
Click to expand...
Yes the rise and fall you see with engine speed is the measurement on the AMOUNT (MASS or VOLUME) of air being drawn into the engine....as the engine speed increase the AMOUNT of air will rise to feed the engine.....the intake air TEMPERATURE will physically remain fairly constant due to the outside air temperature, but the EGR Models will use a theoretical figure for the TEMEPRATURE based on air density and volume....
 
defender300td1 said:
So cut a long story short what reading in the nano it represented by the maf sensor always thought it was air temp that I though was just actualy taking a reading from the maf sensor ???
Click to expand...
As far as I can determine, on MAF engines there is no calculation of air temperature because it is irrelevant, fueling depends on flow and density.
IAT was used pre MAF to calculate density from temperature so the temperature sensor reading is available and needed for diagnosis.
 
Saint.V8 said:
Yes the rise and fall you see with engine speed is the measurement on the AMOUNT (MASS or VOLUME) of air being drawn into the engine....as the engine speed increase the AMOUNT of air will rise to feed the engine.....the intake air TEMPERATURE will physically remain fairly constant due to the outside air temperature, but the EGR Models will use a theoretical figure for the TEMEPRATURE based on air density and volume....
Click to expand...
Except on a turbo engine IAT temperature will rise due to intake air being compressed by the turbo, temperature measurement pre EGR was at the manifold. Post EGR air temp will remain constant as the MAF is pre turbo.
 
Then If these two parameters stay within each other your know that the maf is working ??


: The boost pressure sensor measures inlet manifold turbo pressure and is
displayed in KPa. It should not vary from the atmospheric value by more than plus or minus 5 KPa when
not running or at idle.

Atmospheric pressure (KPa)
: Current Atmospheric pressure measured in KPa, derived from the
pressure sensor
 
defender300td1 said:
Then If these two parameters stay within each other your know that the maf is working ??


: The boost pressure sensor measures inlet manifold turbo pressure and is
displayed in KPa. It should not vary from the atmospheric value by more than plus or minus 5 KPa when
not running or at idle.

Atmospheric pressure (KPa)
: Current Atmospheric pressure measured in KPa, derived from the
pressure sensor
Click to expand...
The car does not run as well as it should or can:)
The BBS diagnostics do not appear to have been modified to show MAF function.
 
Datatek said:
Except on a turbo engine IAT temperature will rise due to intake air being compressed by the turbo, temperature measurement pre EGR was at the manifold. Post EGR air temp will remain constant as the MAF is pre turbo.
Click to expand...
Everyday is a school day...didn't realise that!! I thought on pre EGR the IAT was taken at point of entry AND at the manifold.....then using the theories of Thermodynamics and some clever maths, work out the charge air density, pressure and volume based on the T1 temp and the T2 temp to then measure the energy content of the charge air and adjust fueling to suit to maintain a clean burn....

I kknow we are taking Diesel combustion engines as opposed to Gas Turbines, but when working out fuel maps we use the intake air temp and the temp of the air entering the combustion chamber to work out the fueling required for a given thrust output...this is because as the intake air is compressed through the compressor stage, energy is stored within the charge air, and as it reaches the Combustion chamber and allowed to expand and mix with the fuel, the amount of 'energy' in the charge air needs to calculated else the combustion chamber pressure would increase to much and as the air expands after being burnt and goes through the turbines to drive the compressor...if this fuel/air/energy ratio is incorrect, you can get what is called a 'Runaway Engine' which will run out of control.....

Maybe I am looking at it to complex.....
 
Saint.V8 said:
Everyday is a school day...didn't realise that!! I thought on pre EGR the IAT was taken at point of entry AND at the manifold.....then using the theories of Thermodynamics and some clever maths, work out the charge air density, pressure and volume based on the T1 temp and the T2 temp to then measure the energy content of the charge air and adjust fueling to suit to maintain a clean burn....

I kknow we are taking Diesel combustion engines as opposed to Gas Turbines, but when working out fuel maps we use the intake air temp and the temp of the air entering the combustion chamber to work out the fueling required for a given thrust output...this is because as the intake air is compressed through the compressor stage, energy is stored within the charge air, and as it reaches the Combustion chamber and allowed to expand and mix with the fuel, the amount of 'energy' in the charge air needs to calculated else the combustion chamber pressure would increase to much and as the air expands after being burnt and goes through the turbines to drive the compressor...if this fuel/air/energy ratio is incorrect, you can get what is called a 'Runaway Engine' which will run out of control.....

Maybe I am looking at it to complex.....
Click to expand...

Using the MAF temp reading for fuelling is like wearing an overcoat in Benidorm because it's cold in Glasgow.
 
Datatek said:
The car does not run as well as it should or can:)
The BBS diagnostics do not appear to have been modified to show MAF function.
Click to expand...

Hi data been looking into it they do a maf reading for the petrols and basically as you know the nano is taken from the test book did you or anyone ever use test book and did it have a test for maf on diesels btw I found this and he got a new original one not pattern and all was cured


Diesel MAF
Hi all again,
My dads 2002 p38 diesel is showing a fault for the inlet air temperature, basically it thinks that the air going into the engine is -38. The land rover technician that has diagnosed it has told us that the sensor for the air temperature is part of the MAF, i have checked the workshop manuel and it confirms this. So although the MAF itself is working properly we need to replace it, this is where the problems start. I had loads of none genuine MAF`s on the 4.6 i had and every one was useless causing more problems than the worn out genuine one that was fitted. So we wanted a genuine MAF to fit to my dads car, we tried to order one today only to be told that they are obsolete and land rover no longer do them. I have been on the phone all afternoon and nobody has one.
As i wont see the car untill the week end can anyone tell me who made them (eg bosch, lucas ect) and i can try the manufacterers retail outlets, or can anyone recommend a place i can get one from.
It seems really bad on landrover as they are saying that this car can no longer be repaired and is basically scrap because they dont make the parts any longer.
Sorry for the long post and thanks for any help.
Mark
 
defender300td1 said:
Hi data been looking into it they do a maf reading for the petrols and basically as you know the nano is taken from the test book did you or anyone ever use test book and did it have a test for maf on diesels btw I found this and he got a new original one not pattern and all was cured


Diesel MAF
Hi all again,
My dads 2002 p38 diesel is showing a fault for the inlet air temperature, basically it thinks that the air going into the engine is -38. The land rover technician that has diagnosed it has told us that the sensor for the air temperature is part of the MAF, i have checked the workshop manuel and it confirms this. So although the MAF itself is working properly we need to replace it, this is where the problems start. I had loads of none genuine MAF`s on the 4.6 i had and every one was useless causing more problems than the worn out genuine one that was fitted. So we wanted a genuine MAF to fit to my dads car, we tried to order one today only to be told that they are obsolete and land rover no longer do them. I have been on the phone all afternoon and nobody has one.
As i wont see the car untill the week end can anyone tell me who made them (eg bosch, lucas ect) and i can try the manufacterers retail outlets, or can anyone recommend a place i can get one from.
It seems really bad on landrover as they are saying that this car can no longer be repaired and is basically scrap because they dont make the parts any longer.
Sorry for the long post and thanks for any help.
Mark
Click to expand...
The manual does not say there is an IAT sensor in the MAF, it says that the temperature is derived from the MAF as I recall.
I'm not aware that BBS software is derived from Testbook, the Nanocom is basically the Faultmate software which is I believe unique to BBS, it does not run in the same hardware or software environment as Testbook.
 
Last edited:
Datatek said:
The manual does not say there is an IAT sensor in the MAF, it says that the temperature is derived from the MAF as I recall.
I'm not aware that BBS software is derived from Testbook, the Nanocom is basically the Faultmate software which is I believe unique to BBS, it does not run in the same hardware or software environment as Testbook.
Click to expand...

designed based on the Faultmate MSV-2 which in turn was
originally developed from land Rovers Testbook
 
defender300td1 said:
designed based on the Faultmate MSV-2 which in turn was
originally developed from land Rovers Testbook
Click to expand...

Developed in the sense that it mimics what Testbook does plus quite a bit that Testbook does not do. The actual code is not a copy of Testbook as far as I am aware.
The MAF is made by Pierburg of Germany if you want to know.
 
At last! Someone else with a -38 reading. But... is it normal for the egr (non-IAT) engine to give a reading of -38?? Anyone else with a Nanocom and EGR diesel care to test their Air Temperature?

Ah go on... it'll only take you 5 mins.... I'd do it for you... :)

Nik
 
NikTheGeek said:
At last! Someone else with a -38 reading. But... is it normal for the egr (non-IAT) engine to give a reading of -38?? Anyone else with a Nanocom and EGR diesel care to test their Air Temperature?

Ah go on... it'll only take you 5 mins.... I'd do it for you... :)

Nik
Click to expand...
The Non EGR engine reads atmospheric temperature on a cold engine and rises with load/engine temperature.
 
NikTheGeek said:
At last! Someone else with a -38 reading. But... is it normal for the egr (non-IAT) engine to give a reading of -38?? Anyone else with a Nanocom and EGR diesel care to test their Air Temperature?

Ah go on... it'll only take you 5 mins.... I'd do it for you... :)

Nik
Click to expand...
What I can tell you is that the outside air temperature here is +12C, the IAT shows -38.8 on mine and it runs perfectly. We have to go out, I'll check it again when we get back with a hot engine.
A lot of numbers in the BBS software are not true temperature readings but the HEXADECIMAL sensor readings converted to decimal.
 
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