Exhaust gas temperature

Exhaust gas temperature control

For turbocharged engines, the maximum permissible exhaust gas temperature is a key design criterion.

To protect the exhaust gas turbocharger and the exhaust manifold, the exhaust gas temperature should not exceed 1000 °C for a lengthy period of time.

Since many of the components which influence the exhaust gas temperature have tolerances, thermodynamic adaptation previously took place at 950 °C for safety's sake.

This was achieved by enriching the air/fuel mixture.

The exhaust gas temperature is recorded in a cylinder-bank-specific manner by the two exhaust gas temperature senders G235 and G236.

The Motronic controls the exhaust gas temperature to 980 °C by enriching the air/fuel mixture .

It is therefore possible to largely dispense with the prophylactic enrichment process that has been standard practice until now.

The mixture is only enriched...

• when necessary and
• to the extent necessary.

This means that engine operation with lambda = 1 is possible up to high load and engine speed ranges.