LiU startsida
Abstract |
Detection of Exhaust Manifold Leaks on a Turbocharged SI-engine with Wastegate
Emissions from modern SI-engines are reduced by a three way catalyst.
However if there are leaks in the exhaust system before the catalyst
emissions increase for two reasons. First the untreated emissions leak
out. Second which is worse, due to waves in the exhaust system, oxygen
leaks into the manifold and causes an oxygen sensor offset. The result
is increased emissions as the air/fuel controller makes the engine run
rich.
Here a method to detect leakages in the exhaust manifold is presented.
The sensors used are binary oxygen sensor(s), intake manifold pressure
and temperature, and the air mass flow sensor. Injection time is also
used to estimate air/fuel ratio. Experimental results are shown with
measurements from a turbo charged SAAB SI production engine with
wastegate.
Per Andersson and Lars Eriksson
SP-1704, 2002
Page responsible: webmaster
Last updated: 2021-11-10
