Assuming it is related to something that was done recently, it is possible that a plug wire came off that wasn't fully seated. Is it running rough at all? In other words, does it feel like it is misfiring? This would explain the sluggish feeling and poor MPG.
If not, I think the best bet is to try and see if there are any diagnostic trouble codes. If there are, that will help us figure this out much quicker. If you don't have a scanner, then I would recommend going to any parts store and they should be able to pull the codes for you.
There is a chance that there is a completely new issue that doesn't have anything to do with what was done which again, is why we would need to see if there are any DTCs in the computer.
Let me know if you have any other questions or send me the DTCs and we can go from there. Thanks
Friday, April 26th, 2019 AT 4:50 PM