I have been using an ODBII app for about eight months, the exhaust gas temperature permanently reads 149°C and I thought it was a bug in the app. However, I manged to get the diagnostic software on the car and I have confirmed that car is reading that permanent value, it wasn't the fault of the app.
I figured that the EGT sensor might be broken, so I ran some tests on the sensor connector (behind the intercooler piping on the C3 Pic). The end connected to the ECU read 4.95v with the engine not running. The end connected to the sensor read 18k Ohm with the engine cold and not run for several hours. As the engine warmed up (running for about 3-4 mins), the resistance dropped to 8k Ohm. It was still falling when I stopped the engine and then it started going back up as things cooled. The NTC properties of the sensor appear to be working then
I spent several hours trying to find out what typical resistances are for the sensor and couldn't find anything that gave an indication. Has anyone else tested the resistances on the EGT sensor? If so, what values did you get?
My engine is a DV6D and the sensor is part 1618NF but I imagined that EGT resistance values will be similar on most Cit/Pug/PSA diesel engines.
