Northstar Engines and System Technical Discussion Discussion, Help 06dts Mpg in Cadillac Engine Discussion; Got a new 06 DTS in late Sept. Started out with 16-17 MPG, lately it's 13 to 14. Same type ...
Got a new 06 DTS in late Sept. Started out with 16-17 MPG, lately it's 13 to 14. Same type of driving. Any explanation...on the blog I keep reading about people complaining about getting 21MPG! And I'm driving calmly, no leadfoot here.
I was going to say the cooler weather, and peoples tendency to let their car idle more to warm up. I'm averaging 12.5 MPG with my '94 Deville now that it's cold and I let it idle a bit to warm up. And like your DTS I do get high 20's MPG on the highway easily, but not during the Winter.
Automobile(s): 2002.5 F55 STS, 2014 Explorer XLT 4WD
MD Eastern Shore
Re: Help 06dts Mpg
Something's fishy....I've had my '02 STS for a year and 3 weeks. The day I bought it I reset the average mileage function and have not reset it since. With a combination of 60% highway/freeway and 40% local/city driving, I have averaged 22.3 mpg for a year, 8300 miles. Yes, the mpg goes down to 18-19 in a couple of weeks of slower driving, but crawls back up into the middle 23's during a 420 mile round trip to Norfolk, and that's using 87 octane 10% ethanol crap. (Back country road-running uses 93 octane from a non-emissions county...) We'll do a 1750-mile round trip to FL in 2 weeks, and I'll post what happens doing 85 on 95......A couple of friends own an '03 DTS, drive to FL twice a year, and average just over 26 mpg. Don't idle a modern engine with modern oils to "warm it up".......let the PCM fast idle drop to 900 or so, and then drive conservatively for 3 or 4 miles. Extended cold idling washes oil off the cylinder walls and actually leads to increased wear.
Normal city driving with a fair amount of highway each week ... I'm in los angeles, so no cold weather idle here, and the car is garaged...it's a mystery ... it's almost as bad as the 71 Impala I had way back when ...