I'm Stumped (Poor MPG)
#1
Join Date: Aug 2017
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
I'm Stumped (Poor MPG)
Hi guys,
I thought I'd ask the forum before I break down and commit the ungodly act of paying someone else to work on my car.
I'm having issues with my r56 cooper s (N14). I recently moved from Colorado to St. Louis, and have noticed that efficiency of my car has fallen off a cliff. In Colorado I would struggle to get below 37.5 mpg, even while taking it on a few spirited drives through the canyons. Now that I'm here, even when I try to drive efficiently, I'm struggling to see 31 mpg on flat (by Colorado standards) highways. The service that I've done since owning the car (bought last July) has been pretty simple, just keeping up with oil changes, and I've installed the timing chain tensioner for a stretched chain since it was starting to rattle. I've had an issue with the turbo inlet after getting here, it blew off a couple of times (maybe that issued a stored code in the ECU, making it run a little rich to be safe?) but now that I've cleaned the hose off properly before tightening the hose clamp, I'm not having that issue anymore. The car just ticked over 131000 mi.
Anyways, I know this isn't a lot to go on, but if anyone has a suggestion as to how I can tackle this issue, I'd greatly appreciate it
I thought I'd ask the forum before I break down and commit the ungodly act of paying someone else to work on my car.
I'm having issues with my r56 cooper s (N14). I recently moved from Colorado to St. Louis, and have noticed that efficiency of my car has fallen off a cliff. In Colorado I would struggle to get below 37.5 mpg, even while taking it on a few spirited drives through the canyons. Now that I'm here, even when I try to drive efficiently, I'm struggling to see 31 mpg on flat (by Colorado standards) highways. The service that I've done since owning the car (bought last July) has been pretty simple, just keeping up with oil changes, and I've installed the timing chain tensioner for a stretched chain since it was starting to rattle. I've had an issue with the turbo inlet after getting here, it blew off a couple of times (maybe that issued a stored code in the ECU, making it run a little rich to be safe?) but now that I've cleaned the hose off properly before tightening the hose clamp, I'm not having that issue anymore. The car just ticked over 131000 mi.
Anyways, I know this isn't a lot to go on, but if anyone has a suggestion as to how I can tackle this issue, I'd greatly appreciate it
#2
Altitude. Don't know how high you were (no pun intended) in CO but Lambert field altitude at St. Louis is 605', greater air density. Has a hell of an effect on a golf ball too. That's something to look in to (not the golf *****). The MPG you are now reporting is about what most of us here at 1176' are getting.
#3
Join Date: Aug 2017
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the reply! I think you might be onto something with having more dense air here. I plugged in values from the engineering toolbox (7000' in Colorado) into the fluid drag equation, and found out that I should be getting around 29.5 mpg if I'm ignoring all types of mechanical drag. I think I'll still try cleaning the MAF just to see if there's any potential for improvement there
#5
#6
Not only does lower altitude increase drag, but the higher air density going into the engine means you run a lower throttle angle which also hurts efficiency (contrary to what CAI ads claim). Higher air density also means you make more power, but this also increases fuel economy. So if you tend to drive spiritedly or lightly, either way gets hit.
#7
Trending Topics
#8
Thread
Thread Starter
Forum
Replies
Last Post
Drivetrain Gasoline "Lots" in my intercooler, poor MPG
davidhaas01
Drivetrain (Cooper S)
13
02-16-2010 05:50 PM
R50/53 ONE BALL EXHAUST= Poor MPG
MerchoMini
R50/R53 :: Hatch Talk (2002-2006)
15
07-10-2009 11:14 AM