Hi there,
our Honda Jazz 2007 has failed emissions tests, with the shop saying it smells like burnt oil. The Co was about 0.7, the Hc 300-400 and the lambda value a bit over 1 (so the Co and Hc indicate a rich condition and the lambda a lean condition.
When we took the spark plugs out, they had some oil on it and a white tip. We then put a camera into the cylinders and there was some oil on top of the pistons as seen in the attached image.
We have tested for vacuum leaks, exhaust pipe leaks, the EGR valve, the catalytic converter, changed both lambda sensors, changed the air filter, and the throttle body and intake manifold. All seem fine so it seems more likely that the issue is inside the engine.
Can somebody point us in the right direction as to what the problem could be and why oil would be getting into the cylinders/onto the pistons? Could it be the valve seals/ piston rings?
Note that the car drives and sounds quite fine, but the exhaust fumes have been smelling rich with petrol but there hasn't been black smoke coming out.
Any help is greatly appreciated!
