Got a mondeo in for mot emission failure from another garage failed on co 3.8%,hc 723 ppm,lambda 0.859 that was fast idle ,natural idle was co 1.54% , hc 546 ppm no faults were in the ecu memory had it plugged into ids and first lambda sensor was very erratic so changed the sensor.This made the emmissions even worse co 607 ,hc1010 and lambda 0.789.The cat has been looked at and it is not broken up or melted when vehicle has been fast idling for a while there is faint blue smoke from the exhaust ,if you then remove the plugs and look down the bores all you can see is a layer of engine oil on the tops of all the pistons ! vehicle has covered 90,000 miles and runs really well on road with no misfire .Will the oil in the bore affect emissions that much or do you think this motor is just worn out.Compression tested the motor and the compressions were through the roof at about 200-230 psi but i need to use another guage to confirm this tommorow,have checked cam timing and even looked at cam lobes with the compressions being that high.Oil has been flushed and had inj cleaner through it aswell (forte products)also breathers are clean.

Any suggestions guys
Regards John

Hi

What is the front sensor voltage now?

possible air leak near or before sensor ?

cheers Aidan

what year is the mondeo?? could be an air leak on the little 'T' piece under the coil pack that they suffer from.
sean

Will check tomorrow what front sensor is doing ,it's a 2001 car with the plastic manifold on the front of the engine,also while looking at the engine i found the linkage for the manifold butterfly was disconnected ?? are these prone for breaking up inside manifold??
Regards John

John,
Could be oil control rings worn/seized or worn valve guides.Had similar issue with Seat Toledo and turned out to be the oil control rings seized.This vehicle would show no excessive smoke from exhaust when driving for some reason or was not noticeable, but when checking emissions after 20 to 30 seconds emissions would start to rise at the same time blue smoke would start coming from exhaust.Maybe not your problem but just a thought.Regards.
C.Doyle.

john
yes the manifold flaps breakup and behind the manifold is a breather unit maybe they are linked to your fault
worth a look
martin

""there is faint blue smoke from the exhaust ,if you then remove the plugs and look down the bores all you can see is a layer of engine oil on the tops of all the pistons ! vehicle has covered 90,000 miles and runs really well on road with no misfire .Will the oil in the bore affect emissions that much or do you think this motor is just worn out.Compression tested the motor and the compressions were through the roof at about 200-230 psi""



100% oil control rings are stuck to the piston, these duratecs are renowned for it, giving you your exact symptoms(ie Co rising from idle to fast idle, high HC's, no fault codes .....etc)

Flushed oil with forte and changed oil and filter gave a very hard and long road test with a wynns supercharge treatment added to oil and car passed straight away on the emissions .
Thanks for all the advise guys
John