Jump to content

can someone tell me why?


gp1991

Recommended Posts

How much stop and go and idling does the city driving consist of? That's the major mpg killer in city driving, along with city driving habits (harder acceleration and braking, more on/off the gas instead of cruising at the one speed)

 

I'm not sure what the city mpg should be for your car, but there is usually a bit of a difference between the two.

Link to comment
Share on other sites

Highway driving is very easy on your car, your not giving it much throttle and your maintaining speed which doesn't take much fuel... however in the city, you are not going very far (think about How long it take to drive 30 miles in the city, when its a half hour on the highway)... and at the same time your revving up to get going which takes a lot of fuel... your rpms are around 2-3k at almost all times, in the city your doing 30, on the highway your doing 70... make sense?

Link to comment
Share on other sites

Age and mileage can play a large roll in the disparity between the two also. When your car is older and has many miles on it, the engine can be a bit tired and that causes you to push it a little harder around town. My car nets 25mpg city and about 33mpg freeway (Summer). Obviously the size and congestion of the city causes a lot of difference as well and may play the biggest factor. I live in a smaller less congested city so my idle times are usually pretty short, also I am typically pretty light on the gas most of the time. Short trips can lower the mpg even more. The car gets the best mileage when everything is warmed up. Its a plain fact that if the car isn't in closed loop operation it isn't getting the best mileage. Winter time my mpg drops a ton because of long idle times while I am warming up the car, plus adverse weather conditions will lower mileage. I honestly don't even check mileage in the winter months.

Link to comment
Share on other sites

I've having no problem getting about 23MPG city in my 3.1 Grand prix. I went WOT one time in my GP since I bought it and was amazed at the lack of power over 4k RPM. Sounds good! lol

 

I was averaging about 33mpgs out on the highway and after a 850 mile trip I ended up getting 26.0MPG.

Link to comment
Share on other sites

Well city, depending on how heavy footed you are your always fluctuating from idle speed to how ever hard you hit the gas. For me it would be about 600RPM - 2500-3000RPM. Think your always doing that and on the highway your hitting 2000RPM, at least I do... it does make a big big difference

Link to comment
Share on other sites

My '02 3100 has been averaging 26 on the dot according to the DIC on this tank, probably 30/70 city/highway. I'm REALLY easy on it in the city though, lots of coasting to red lights and light acceleration. Even with that, my average MPG drops rapidly with in town driving. 20 or more miles of stop and go driving will easily pull my average from 26 down to the 22-23 range.

Link to comment
Share on other sites

does any one know why i get 31 mpg on the highway and in the city i get 15-16? seems like a big difference to me.
i get these same numbers. my city driving is very short drives, a mere mile to work. but i get on the freeway, set the cruise at 65ish and im hitting 30mpg.
Link to comment
Share on other sites

These cars are (relatively speaking) fairly aerodynamic and will cruise on the highway pretty effortlessly, but they're not light cars. I routinely averaged 29-30mpg in the Regal with the old L27. I usually averaged 17-18mpg with all city driving. Now, I'll be lucky if I exceed 20mpg city/highway. 3.29 gearing and a 3.4" pulley on an L67 doesn't make for a great average fuel economy. I believe I'm getting around 16/24 city/highway as I have averaged 23-26mpg highway on longer trips.

Link to comment
Share on other sites

The damn trip computer always made me watch my throttle. Id set it to instant economy and drive myself nuts. Slow slow slow acceleration and early shifts.. I got good mileage but i was too ocd about it. Now days I set it to exterior temp haha.

Link to comment
Share on other sites

If it's an auto trans, part of the problem (?) is it doesn't get into OD until you're going faster than ~45MPH. Around town, either keep it under 35MPH or drive faster than 45MPH.

 

I've noticed that in the city, the engine is turning RPM's in 3rd like it's cruising down the highway in OD.

 

Like Extreme stated.....these are heavy cars. Have you ever tried to push one off the road after it died?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...