Hi guys

Ive recently bought an 04 plate Mondeo 2.0 TDCI 115 with 113k on the clock, that's averaging 30mpg. That seems ridiculously low to me so...

I've had the injectors professionally replaced
I've replaced the EGR valve and cleaned the inlet manifold, replaced the fuel filter, and air filter
The air filter to turbo hose was split - I've replaced it
The EGR to inter cooler hose was split - I've replaced that too

But it's all made very little difference and now I'm stuck for ideas. Can anyone suggest anything I may have missed?? I'm beginning to think it may be something electrical but is there anything mechanical I should check?
Cheers

 

town use or motorway i found mine going to read 40mpg town but back up to 56 motorway so drive on keep the revs over 1.7k seems to be best range !

 

Probably about 75/25 town driving but surely this engine should be averaging more than 30mpg even if it were completely round town?

It seems to have a slight stutter around 1500 - 1700rpm but only in 3rd/4th... Very confusing!

 

has the car got standard size wheels and tyres, is the onboard computer accurate?

Do a full tank calculation

 

Yep, standard size wheels/tyres... I get just shy of 400 miles to a full tank. What does everyone else get out of curiosity?

 

how much to fill up?
i know its different but my tranny get sabout 500 miles to 75 ltrs which i beleve is about 35mpg (fuel card printout)
my old superb would get 50+ mpg in pretty much any driving wether it was 100mph a roads or shop to shop on a saturday and is my laiden tranny can do 35mpg with the boot usually down and ladders on the roof there deffo summet up with yours

 

It's a 60 litre tank in the Mondeo I believe... Gets around 395 miles from full to fumes. Apparently that works out just shy of 31mpg on average. Parkers says it should reach about 38mpg combined.

I've tried just about everything I can find via google regarding excess fuel consumption on this engine so just wondering if anyone can suggest anything else or if my expectations are too high

 

Yeah, something's not right there. Even one driven very briskly should be geting 35mpg minimum.

Does the car feel down on performance at all?

Bit of a long shot but disconnect the battery overnight then go for a long run.

 

Yeah it does feel a bit weak...

Tried the battery thing as I read somewhere it may be worth clearing the ECU - hasn't made any odds though :-(

 

It should feel quite 'punchy'. Even the 115 goes well, as it's a torquey engine. You've obviously got issues somewhere. Probably wisest to go through the simple things first.

When was the air filter last changed? Or the fuel filter?

Have you got any fault codes coming up?

Has it always felt this way?

Does it make any odd 'whooshing' noises?

What condition are the boost pipes in?

Does your EGR have electrical an connector on it? If not consider blanking it off to see if it makes a difference.

 

Cheers for the advice Dan, exactly what I was looking for!
I'd say it's no more pokey than my old Vectra DTI but easily reaches higher speeds. I've changed the fuel and air filters in the last 200 miles.
Not getting any fault codes (which I guess at least means there's nothing majorly wrong?)
Nope, no whooshing noises, but the slight judder right where I'd expect the turbo to be kicking in is curious...
I've changed the hose going from the inter cooler to the EGR valve and the one from the air box to the turbo as both were split... Are there any other hoses I should check??
The EGR valve has the electrical connection so blanking it isn't really an option... Though I have replaced it as it was sticking

Cheers Dan

 

My 130bhp Mondeo does around 45-48 around town and 48-55 on a run i have in the past seen 60+ on a long run, on 60 litres a full tank i get between 550 and 600 miles to a tank and the car has done 215500 miles


Brian

 

Some do seem to be more fuel efficient than others, and my 130 is no where near as efficient as Brians. 130s do seem to do better mpg than the 115s, but 30mpg is way too low, even if you're kicking the crap out of it.

Are the brakes binding? Either jack it up and spin the wheels, or see if any of the wheels are particularly hot after a long drive. Is the cat, or exhaust blocked? Is there a lot of black staining on the bumper by the tailpipe?

 

Good shout on the brakes - ill get them checked at some point over the weekend...

No staining on the bumper though - does that indicate the cat should be ok? There is some black smoke when revved but not enough to see while driving. It was pointed out by the mrs when she followed me

Put Ł40 of fuel (144.9 a litre) in it when it said it had 30 miles left and 170 miles later we're back to 30 miles left... Definitely something wrong there!

Cheers for the advice so far Dan - glad I joined this site

 

Could the DPF be blocked? Not sure that a blocked one would change the mpg like.

 

Interesting - unsure whether mine has a DPF or if it's a EuroIV. Is there an easy way to tell?

 

Not a clue. Owners manual maybe?

 

Haha fair enough mate. Sadly I don't have one... Another thing to check though cheers

 

No, it doesn't have a DPF.

They all smoke 'a bit', and it's common to see a noticeable puff of smoke if you boot it (particularly at night you'll see it in the following car's headlights).

Black smoke would just suggest overfuelling - mine does it, particularly since fitting a decat and removing the EGR.

I'd also suggest doing a few 'brim to brim' fill ups to calculate the mpg properly. If you've got an iPhone there's a useful app called 'Road Trip'. There's probably something equivalent on Android.

This is what mine gets...



Not great, but then the majority of my driving is done along country lanes, and in town.

 

My money is on the thermostat being buggered - if it's open and the engine over-cools then it will not hit it's efficient running temperature (obviously) and this will have an adverst effect on MPG.

 

How would you know its faulty other than removing it and testing it?

 

Does the car's temperature drop if you coast downhill? And does it take ages to warm up?

The gauge should sit in the middle. If not it could be worth swapping both thermostats.

 

Wouldn't this cause the engine to run a little lumpy, maybe at idle or speed?

 

Not necessarily. Even a healthy engine can be a bit lumpy at idle. It's not exactly the most refined engine out there!

 

I will say one thing though and that is that my MPG went up alot when i cleaned the MAF sensor.

 

When you had the injectors replaced do the do an injector pilot correction?
I think if it wasn't you should try it may help.

 

Didn't think you could do pilot correction on the old Delphi?

You can on the post 2006 Transits etc.

 

Cheers for all the info guys - calculated it at 30.9mpg after 200 miles mixed motorway and town driving :-(

The thermostat was replaced very recently as it was leaking - I don't have any issues with the temperature gauge... Sits nicely in the middle. Probably takes around 5mins to get there. Although I am intrigued by "both" thermostats... Two?!

I've also cleaned the MAF sensor (the one near the air filter?) when I changed the hose as it was filthy - sadly made no difference.

Next ill be checking the brakes aren't binding but none of the wheels seem particularly in comparison to the others. Still... I'm desperate to solve this as its so frustrating!

I've downloaded that app too - seems very useful so will definitely make use of it, cheers!

Some great info coming out of this, cheers fellas

 

30 is way way too low, but you already know that. Could be worth your while booking it into a Delphi specialist for a diagnosis.

Also, cleaning your MAF isn't always a great idea as it's very delicate. If you've damaged it it could account for your abysmal MPG>