AAP sensor reading not correct (?)

Has anyone noticed that the AAP readings via Nanocom (temperature) is somewhat higher than the actual outside temperature?

My inlet system is a bit longer than the standard version but I see to have some 10-15 degrees to high readings ..

Lars

...where the heck did you get an AAP temperaure reading though? ... cos AFAIK there's no reading for that on any tester

�� so the temp reading is at the inlet manifold after the intercooler .. Makes sense ��

the only reading you can see with tester is from the MAP/IAT(inlet air temp) sensor... we generally call it MAP but it's double purpose sensor, it reads the inlet air temp too for the management and that's the temp reading you see which is normal to be higher than the ambient temp, you'll get even more difference than 10-15* when the engine is hot and under load... the AAP sensor's temp reading is not part of the diagnostics instrument mode so you can't actually see it, you'll get a fault code if something's wrong on it's circuit but that's all.

Back on track

that's why it's important for the MAP(IAT) sensor to be clean cos that gunk on it lowers it's temp reading and affects the turbo management/fueling...even the pressure reading is based on the inlet air's temperature cos the sensor is not pressure sensitive... you can figure that out if you touch it

How can it not be pressure sensitive? It needs to be, as the turbo pressure changes ...

Lars

The manual says

The MAP sensor works on the piezo crystal principal. Piezo crystals are pressure sensitive and will oscillate in
accordance to changes in air pressure. The MAP sensor produces a voltage between 0 and 5 volts proportional to
the pressure level of the air in the inlet manifold. A reading of 0 volts indicates a low pressure, a reading of 5 volts
a high pressure. The IAT portion of the sensor works as a Negative Temperature Co-efficient (NTC) sensor. As air temperature
rises, the resistance in the sensor decreases. As temperature decreases the resistance in the sensor increases.
The ECM compares the voltage signal to stored values and compensates fuel delivery as necessary.

i stand corrected then... i forgot about that and spoke out of memory...nobody's perfect

i made a confusion cos there are older MAP sensors(not Td5) which are working on the temp difference in the inlet as there's a strong link between temp and pressure based on PV/T=const universal formula...sorry for missleading you...it happens but not very often

No worries
I agree there is a link but here you have two variables ..

yes but the air's volume is constant => P/T = constant so as the T varies so does proportionaly the P...believe me there are so called "pressure sensors" based on temperature measurements, not the case here just that there was a mixage in my head knowing about them and forgot about what RAVE sais.