2004 Xc90 very low gas mileage even with new fuel pump

Sounds like an evap system leak.

Thank you Ford_fanatic87. out of curiosity my volvo guy is married to the computer system detector indicating a code and since no check engine light came on in addition to the the detector system, is there a possibility this evap issue won't signal a code or is not tripping a code because there is a malfunction somewhere?

Its possible depending on where the leak is and the size of it

As long as it's not leaking enough to be "outside of specifications" it wont throw a code

Thank you so much Ford_Fanatic87! I know something is off. for sure and I'm hoping that's it! I know when I push on the gas it takes more of a push to get it going than it used to and turning the key struggles every few times in the week. not sure if that's connected as well, but the evap leak will take me to a new place. I'm so appreciative of your time!!

Let us know what you find out and we will see if there's something else amiss that might also be causing your problem

Thank you! my guy still wants to wait for a code to pop up. aggh! so , I have to make the choice to just replace and cross my fingers it was the thing causing the issue, or hold for a code. frustrating .

A visual inspection of the lines will show if there is a break in the line, even if a code isn't given....best of all, if you look yourself or have a friend who can be trusted, it won't cost anything unless you find a problem.

I didn't think it was an easy visual to do. I thought the line was within the underbelly. but I'll Google. thank you!!

For the most part all of the lines are easy to be seen