97 850GLT only 15 MPG

Old Bakelite · Post by **Old Bakelite** » 09 Feb 2008, 17:19

First off, is there a way to search MVS (?) as I think I may have read something about this but can not find it and hate to ask if this has already been addressed.

Anyway. it seems I am only getting 15 MPG......my first 120 miles took 8 gallons......mostly too and from work (3 mile journeys each way), but about 20% highway in between. I do use Premium petrol.

I seem to recall reading on this site about an additive that really works.....is this really true and what is?

Should I be looking at some other reason?
155k.

Cheers.

Post by **MadeInJapan** » 09 Feb 2008, 17:33

The Search MVS window at the top right of the screen works but it isn't the greatest search engine. Sort of hit or miss.

I notice you're from Rhode Island. If you're having sub degree temperatures up there, I'm afraid 15 may be about the best you're going to get. Others might disagree but I was getting 15~16 a couple of weeks ago myself when it was really cold down here in TN. Now that it's warmed up a bit, I'm back up to the high teens again. I'm also at about 20% highway and have short trips lately and I considered my S70 to be well tuned as well.

I would be hesitant to try most additives.. you could however try a good octane booster and cleaner such as Chevron Techron (sold in a bottle at the auto parts store) and it could restore some mpg's by cleaning your injectors, but I really doubt it will be too noticeable.

Post by **JRL** » 09 Feb 2008, 17:37

City driving with never getting it warmed up, that's about right.

If you do a COMPLETE and proper tune up, change ALL the filters, add some air to your tires and making sure that the entire engine is like new in all aspects, you may get 2 MPG more!

Post by **lewismug** » 09 Feb 2008, 20:12

Guys, I'm not exactly sure, but I'm getting somewhere in the neighborhood of 27 or 28 mpg on my 99 S70 2.4l n/a. MIJ, I drive 180+/- miles per day almost all highway. Would all highway driving make that big of a differnce between your high teens and my high twenties? I'm just south of you MIJ in north Mississippi, and I didn't notice a drop in my mpg when the temps dropped a few weeks ago.

Post by **MadeInJapan** » 09 Feb 2008, 21:02

When I drove my 100+ miles a day (almost all interstate) I was getting nearly 500 miles to a tank of gas. Yes, all or almost all highway miles does make that big of a difference. Now that I have a different job locally since Sept., I hardly drive over 5 or 6 miles at a time. Extreme cold seems to have even a greater impact when driving is city or almost all city driving with these cars.

Post by **JRL** » 09 Feb 2008, 21:07

lewismug wrote:Guys, I'm not exactly sure, but I'm getting somewhere in the neighborhood of 27 or 28 mpg on my 99 S70 2.4l n/a. MIJ, I drive 180+/- miles per day almost all highway. Would all highway driving make that big of a differnce between your high teens and my high twenties? I'm just south of you MIJ in north Mississippi, and I didn't notice a drop in my mpg when the temps dropped a few weeks ago.

Yep.
I have a 99 V70 (na) for sale. Highway is about 26-28 and city is about 20.
Turbo motors get WAY less MPG and the city vs. hwy mpg is huge, about 8-9 mpg!

Post by **MadeInJapan** » 09 Feb 2008, 21:10

I agree with JRL...and to add to that, my S70 has an upgraded ECU and I like to use the turbo so everything adds up to less mpg for me in the city.

Post by **meine39** » 09 Feb 2008, 21:19

My experience with our 95 Wagon mirrors JRL's comments - the car got 15.5 MPG in suburban driving when we purchased it two years ago. I have since completed all the "Stage Zero" tune-up maintenance (plugs, wires, cap, rotor, fuel and air filters, TB cleaning, EGR cleaning, new airbox thermostat), and the MPG rose by 2 to 17.5.

I could be totally off base here, but I've never seen any mention of variable valve timing with the 20 valve motor, and I wonder if the lack of VVT impacts the fuel consumption.

I've never checked highway mileage - this car is the teenager-mobile at our house, and my Home Depot runner on the weekends...

Old Bakelite · Post by **Old Bakelite** » 10 Feb 2008, 06:06

Thanks MVS......I'll keep an eye on it as the weather warms up......although I think wife's 850 T5 averages 21.6 according to the trip computer.

Post by **MadeInJapan** » 10 Feb 2008, 06:13

Variable timing came out in '99 (thus the new tensioner and different timing belts with longer change intervals). All of our Volvo's '98 and older didn't have that and yes, I would say it does impact our mileage to some degree. My wife's '04 V70 gets much better mileage with city driving- about 20~21 no matter the temp. outside.