2005 xc90 2.5t fuel efficiency loss
 

Hello, thank you in advance for any advice. I am being given our 2005 Volvo xc90 2.5t. I basically use this Suv like a truck. It has 165000 miles, and gets regular maintenance, oil and air filters. Im leaving for the summer and need to make it reliable again. The only problem i have seen it a loss in fuel efficiency, from about 22 down to near 15/16.
What can i do to get some of this back? I dont have time to do the work myself needing this done in a week. I was considering spending money on rings, but would love to hear any advice as to what should/can be done. If you could spend 1000 on a suv of this age, where would it go?
Thanks again for any advice.

You're not gonna put piston rings in for $1000.

What kind of maintenance history does the car have? Spark plugs, air filter and fuel filter are all things that are easy to replace that can cause lower fuel economy. If the throttle is dirty, it can also cause lower fuel economy. Is the check engine light on?

02 sensors

I was afraid that was the case, the car has always been maintenanced at a local shop. Not a Volvo expert. I plan on calling a Volvo specialist this week and getting the car in
And hearing his advice, but figured it wouldn't hurt to have a little of my own knowledge before I went in.

Maintenance problems over the years:
Oil catch can was clogged causing emense loss of power.
Hose from turbo to intercooler was cracked and loss of power.
Both these problems fixed.
On the inside of the car, the shifter will drop into drive, but when turning over bumpy road or when touched will shift over into "Manual" un restricted. (I think a retaining spring broke loose".

That's about all I can think of. Most of its 165000 are hwy miles. Thanks for anything else you could think of that would cause a loss of gas mileage, or for tips on what I should look out for next.

Pcv and fuel filter

Rings? These motor rarely need rings, especially if they have had regular oil changes.

Do you have a CEL?

Is it possible it's just not rolling easily? Worn out wheel bearings can cause a dramatic loss in power. Does it roll easily in neutral?

if the rings were bad you would see blue tinged smoke out the exhaust.

Any odor of fuel? Another recent thread mentions the common fuel pump crack which causes constant leaking. That would certainly affect fuel economy.

Here's the thread... https://volvoforums.com/forum/volvo-...nterior-72259/