Help with fuel economy

[bomhour]

I just bought a 2010 X35d and contrary to what most folks here are experiencing, my fuel economy stinks with an average of 18 mpg. I have brand new Bridgestone tires, and a new oil change. I added fuel injector cleaner this last weekend. I checked the air filter and it's practically new. What else should i check before my 1100 mile road trip this weekend to help with my crappy fuel economy? My wife mostly drives the car and she goes easy on it. it has massive power according to my weekend excursions. Everything seems to be working correctly and there are no warning lights or anything like that.

Any tips are appreciated.

Thanks,
Adam - Billings, MT

[TerminatorX5]

welcome aboard...

it is my understanding that the diesels are very thrifty... i get about 18 MPG on my 4.8is, which is very thirsty...

I do not know much about the diesels, but i would suspect that engine needs some loving - clean up the injectors or whatnot, couple hot oil changes, to see if there is any sludge built up in the engine... i do not know about glow plugs, but if there were spark plugs, i'd replace them too...

lets see if there are any diesel gurus out there who can chime in...

again, welcome aboard

[seattle]

OP, is this purely city (although "city" sounds funny in context of Montana ) or highway miles?
I can see how you can get 18mpg driving in LA or Manhattan. After all, the vehicle is rated 19mpg city.

How do you calculate your MPGs? Merely by what computer tells you? How many miles do you get on a full tank?

What diesel type do you fill up with? Hopefully not B20..

[bsaunder]

My 2013 was doing that for a while, after previously getting 21-22mpg in the same environment. Turns out I had a very clogged up turbo (soot) and my turbo control module wasn't working correctly. Many egr codes later and finally an engine malfunction and the dealership got everything fixed, (crossing fingers). In the process, I got a new egr sensor, new egr valve, new maf, new air temp sensor, new air filters, intake completely cleaned and resealed, all turbo pipes an intercooler cleaned and resealed - so it could have been all the above.

Now that I haven't been all that helpful - it could be some simple variables such as choice of tires, inflation of tires, quality of fuel, roof rack or anything else disrupting air flow, lots of short distance miles, etc.

[conedoctor]

On our 2010 with 146,000km we get 22.5 mixed and around 30 on the highway.

We have the 18 wheels, our mixed is 50/50.