What is required for a tune-up? Do I need to replace ignition coils?

2005 S60 T5 with 150K mi. Runs good but low mpg @ 22.

2003 S60 with 187K mi. Owned since 45K with no plug or coil replacement. Runs fine 29 mpg.

 

Plugs are due every 60,000 miles so I would definitely do plugs on both. Coils are common to fail but don't need to be replaced if they are firing.

Fuel filter is also overdue, due at 105k.

 

Thanks

Any suggestion to increase MPG on T5?

 

My 07 2.5T gets about 24 MPG at just about 100k.

Definitely replace the plugs and fuel filter. Make sure the air filter is clean and it might be a good idea to clean the throttle. I just cleaned minor today so we'll see if I get a significant jump in MPG. It wasn't too carboned up.

 

2008 S60 with 67k, struggles to get 19 mpg.

I was thinking plugs, fuel system cleaner, air filter. Anything else this side of 100K?