complacentsee

VAG block 112 IIRC. But it isn't labled as you would think. There is EGT data, which is estimated based off primary O2 sensor resistance. And there is also the real data, but it is mostly useless since if everything is working right, you won't hit EGTs high enough to get within the sensors operating range.

slappy_dunbar

Ross-Tech shows it as block 112 alright, but this looks like a sensor located after the turbo.

Am I wasting energy trying to tap into the vehicle's sensors for manifold temps? It sounds like it might be a good idea to install a separate, dedicated sensor in about the same spot.

complacentsee

To sum up of the stock sensor.

It is a k-type thermocouple attached to an electronics package. The electronics package does the high sensitivity measurments on the thermocouple. It also provides diagnostics for failure. It uses a pulse width modulated signal to send it's value to the ECU. For what ever reason they decided to use a narrow temperature range on the output.

slappy_dunbar

Ultimately, the question of manifold EGTs is discreetly handled by the 2.7t ECU. This explains the relative black hole of information on this -- the cars are designed so we needn't worry about it so much. Regardless of the built-in safety measures I'm still interested in knowing first hand what is going on in that part of the car.

Thanks a lot for clarifying this. It almost sounded like the info was easily obtained, but it now is clear separate sensor(s) is what's called for.

complacentsee

You could disable the EGT enritchment map. (zero it out) then remove the egt sensor and put a real one in it's place.