Mondeo V6 MKIII

[Kiwi93]

I have just had my car serviced and the MPG has dropped from 27.5 down to 22.5 and is still dropping. Ford cannot find anything wrong but my question is well is there somethingelse I need to be looking at. No problem before service now its very thirsty. Can anyone please help me?

[Blackwhite]

It is colder now ;)

22 MPG it is not so bad for V6 mate.My Passat 2.0 petrol was 25 MPG

[Kiwi93]

It is colder now ;)

22 MPG it is not so bad for V6 mate.My Passat 2.0 petrol was 25 MPG

I appreciate the weather would have a part to play, but the drop has been so quick and it is only since its service this has happened.

[InstructorPiggy]

no other faults or change to drive?

Piggy :)

[Kiwi93]

no other faults or change to drive?

Piggy :)

the car seems to surge between 20 & 40 mph. Fords agreed with that but can't find the fault.

[InstructorPiggy]

sounds like fueling problem.

Try checking that the air flow sensor hasnt been refitted wrong way round (assuming they checked the air filter)

Check the air temp sensor while you are there, thinks it in the airbox/intake soon after filter, check connection/damage.

Also check the coolant temp sensor, ensure not damaged and still connected.

After that, gota look at Lambda sensors, throttle position sensor and fuel pressure.

Piggy :)

[Kiwi93]

sounds like fueling problem.

Try checking that the air flow sensor hasnt been refitted wrong way round (assuming they checked the air filter)

Check the air temp sensor while you are there, thinks it in the airbox/intake soon after filter, check connection/damage.

Also check the coolant temp sensor, ensure not damaged and still connected.

After that, gota look at Lambda sensors, throttle position sensor and fuel pressure.

Piggy :)

Thanks Instructor piggy for the advice however we have checked all you suggested and couldn't find the fault. What else can you suggest? The mpg is now down to 21.7 from 27.5.

[fish4tea]

Thanks Instructor piggy for the advice however we have checked all you suggested and couldn't find the fault. What else can you suggest? The mpg is now down to 21.7 from 27.5.

Possible there might be a leaking injector thats not cutting off properly

[InstructorPiggy]

Possible there might be a leaking injector thats not cutting off properly

true...but this should show up on the lambda sensors...you sure you have checked these?

there may even be 4, 2 per bank, pre and after cat! :)

gota admit...would so be looking towards air flow tho...has it been checked on a scope?

[chris bowman]

may seem worse if ure average mpg has not been reset since u had the car which means the figure considers many thousands of miles including dual carriageway and motorway driving. now that the car has been serviced the mpg may have been reset and since then uve just done town driving which is mopst uneconomical on the scale of things. experienced the same myself on my tdci only to a lesser degree as mine is diesal

. try it for a while and see what u think.