03-22-08, 11:27 PM
I bought a dts for my mom in dec, real clean one owner car. The car drives beautiful and all but I've noticed that after a few fill ups my average mpg is 12mpg. Now I wasnt expecting a hybrids fuel economy, but when I researched the car it said anywhere from 18-27. I understand that I wont get anywhere near the original mpg rating but its definately completely off. I also notice that it drinks about a quart every 500 miles or so, is this normal ? I was wondering if its something common for the northstar or if its something that I should have checked out.
Mileage varies greatly depending on how and where it is driven. All city driving will be low, but not doing any, I am not sure what it should be. Check for a leaking FPR. See the Tech Tips section.
Go to the top left of this page. Click on Technical archives (not to be confused with Tech Tips) and read up on oil consumption.
03-22-08, 11:59 PM
What year DTS? How many miles? This is the "sport" model and has a performance final drive ratio (3.71:1?) with torque convertor lockup at highway speeds, so you're behind the power curve right there. City mileage will vary from 10 - 17, mixed city/suburban from 15 - 19, and open road from 22 - 27. Mostly city driving? Use 87 octane.
Read a lot of the Seville, Deville, and Northstar performance threads and find out how to clean out the engine by doing controlled WOT (Wide Open Throttle) runs. If the car has been babied there's a good chance that it will use oil: Northstars like to RUN and you need to clean it out. Don't fill the oil to the top of the hashmark on the stick.....keep it at halfway only. Use the owner's manual recommended viscosity oils, and don't get creative. The engineers have already done their work. (The 18 -27 mpg sticker figure is a pipe dream concocted by the EPA and the manufacturer in order to keep the CAFE bureaucracy at bay.) You should get a recall/warranty printout from the selling GM dealer...service desk printout with your VIN.
Do some homework in here....there's just tons of info to read.......I just saw the "00caddie...."