Dear everyone,

My brother got a 2007 Ford S-max with 2.0 Petrol engine. Its currently consuming a few liters of oil in a month. No blue smoke on idle. Full gas over 5k rev, blue smoke. PCV valve or worn piston rings? What do you guys think and how to test it?

Thank you!

Mvh
Oliver

It is most likely to be worn Piston Rings/Bores.

The old school way of checking this is to do a Compression Test, note the results and squirt a bit of Oil into the Cylinders and do another one. If there is a big difference then it is likely the Rings/Bores are worn.

If it was a Valve guide problem then the Smoke would be worse accelerating after the Overrun, also assuming that there was little difference in the above test.

With a 17 year old Petrol Engine it is likely that everything will be past its best. 

And, not that it changes the overall opinion above (I'm Old School), but there's no evidence of a leak as "a few litres a month" is IMHO, potentially a massive consumption depending on mileage being covered?

thank ou for the replys. correction is that the car uses about 1 liter in a month. still high. a youtube video suggested to do an italian tuneup to free up the stuck piston rings. driving high rpm under load for 50-100km

28 minutes ago, pike409 said:

thank ou for the replys. correction is that the car uses about 1 liter in a month. still high. a youtube video suggested to do an italian tuneup to free up the stuck piston rings. driving high rpm under load for 50-100km

That is always good for an Engine but I don't think you need to drive it like that for quite as long and it is better if you don't keep it at the same revs all the way, a little variation is likely to be more beneficial. 

Also if a car is used for mainly short journeys, a long run at Motorway speeds would normally do it the world of good.

Really need to find out where it is going so definitely no leaks? (engine undertray needs removing to check?)

Redex upper cylinder lubricant to try to free off anything stuck?

Then compression check as above. If lots of blue smoke it is avoidable meaning potentially MOT fail/illegal (if I remember correctly?)

https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/introduction

f. The vehicle emits substantial quantities of avoidable smoke.

Depends on the tester?