Poor fuel mileage

[thunderstruck1]

My best was a trip to Nashville from Chicago and back over Memorial Day where I got a pencil and paper calculated 41.7 MPG. I drove either 65 or the posted speed limit, whichever was lower. One major problem is 6th gear is way too short. The .91 gear is not needed for highway cruising, they should have put in a taller 6th. With the right gearing the GTI would be a 43-45 MPG car on the highway. Disclaimer, my car is chipped so YMMV.

 

[jmp4golfvw]

Has anyone had poor fuel mileage prior to their car being broken in? My TSI 1.8t has just over 800 miles on it and I'm experiencing fuel mileage well below what I expected and below sticker rating (hwy). My commute is almost ideal for topping out mpg and with every previous vehicle I've been able to meet or exceed its rated highway mileage on my commute.

On my first full tank the computer calculated 32.4 and I actually had 28.4mpg. I'm a couple hundred miles into my second tank and the computer is showing 32.2mpg.

I am disappointed in both how far off the computer's calculation is and at overall mpg at this point. I'll continue to track.

I'm experiencing the same thing and I'm wondering how common this is, because I'm starting to hear of this more and more. I just can't figure out how I'm getting mileage that's consistently this far under its rating, especially when driving both city and hwy. I haven't been able to get anything close to the combined mileage rating of approx 29 +/- mpg. I'm hovering consistently around 21-23 mpg, which is crap. This is all done with zero spirited driving, just me in the car, nothing in the hatch and no A/C on, and even while taking 2 hour hwy trips each way (drive to Greensboro drop my son off and turn right around to go home) once a week, while using cruise control and I believe I've maxed out at 31-32 mpg +/-. So I'm no where near the 34 mpg mileage claim.

People refer to "perfect conditions" when explaining why the ratings can't be reproduced, but if an owner can't reproduce even, fractionally, the claimed mpg, then I'd say it's not representative of what that car can try max out at....looking like another case of false advertising to boost sales. I would have definitely gotten the GTI if I would have known I'd get such poor mileage.


Sent from my iPhone using Tapatalk

 

[zx5go]

Just passed 1000 miles on the odometer and filled up. Computer was showing 32.2 and it was actually 29.1 mpg. Horrible imo. I can't believe how much fuel this engine burns sitting at a light/stop sign and during acceleration (based on viewing the instant mpg during acc and watching the avg drop during stops). I'm still hopeful it is set to run a little rich during the break in period. Really babied it on the way home after the fill up but that had me dropping my speed down to 40 mph in some spots. Still was only able to get the avg since refuel up to 38.4mpg and with the inaccuracy that is probably 35-36 and there is no way someone should be expected to drive the way I was driving and if there were any traffic I wouldn't be able to. If I am unable to get my commuting mpg above 34 I'll sell it and move on to something else.

 

[jGTIw]

I've been getting 38-39MPG on 300mi weekend trips, 65-70 mph mainly on cruise; included a bit of city driving and a short drive with flooring it at 4000rpm. Pretty impressed. Computer has been within 1 mpg of pencil/paper calculations.

Sorry to hear about the 1.8T issues.

 

[lucyfek]

If you get less than 30mpgs you really need lighter shoes
Slow down (but even then, doing ~80mph will easily net 34mpg) and drive to get get mpgs you wanted. Use center display for current mpgs readout for guide - it may be off by few but you'll see trends and develop optimal driving techniques. Winds will drop your mileage and so hills (if you try to keep the speed up hills). Don't idle, move. Get the MT, too late for you. On my 35 mile commute I average 40 and more (between fill-ups, and this includes some city driving).

 

[thunderstruck1]

Have you checked tire pressure? Inflate 10% less than maximum number on sidewall to bump economy when they're cold. I have a pump in car driven off lighter socket which makes it easy.

 

[desol8tor]

It definitely gets better. I have 3600 miles now and I can get around 34mpg with a 35 mile commute that has 10 miles in stop and go traffic and the highway portion goes over/down a massive windy hill (weeee).

I feel like I have room for improvement as well, maybe until I hit 5k miles.

 

[haktical]

I have a GTI (which I would expect to be a little worse than the TSI), and on a trip just over 300mi each way this past weekend the computer told me I averaged 35 mpg on the way out and 38 on the way back. Mix of ~60mph on curvy mountain roads and ~75mph on the interstate. No cruise control used, some uphill, some downhill, pretty good mix of driving. Just hit 1k miles, for reference. If you're getting less than that in the TSI, you either have a problem or a heavy right foot

Hand calc for the trip out comes out a bit lower, around 32 or so, I didn't do one for the way back, but sometimes pumps don't fill equally (I never top off past when the pump stops) so I expect a little variance.

 

[zx5go]

desol8tor, thanks for the feedback. That is the type of info I was hoping to get from a few members. I'll keep tracking it and let everyone know where it goes.

 

[thunderstruck1]

Fuelly is the best way to track over the long term, and you can give others data to compare with.

 

[zx5go]

thunderstruck, tires are at proper pressure and I track all my vehicles in fuelly. There isn't much data in on the 2015 1.8 yet. I was hoping to use this thread to get more user feedback.

 

[Skips]

Some members posted here that coasting in gear vs in neutral can boost your mpgs (I'm in the process of testing this myself):

http://www.golfmk7.com/forums/showthread.php?t=8499

I also read somewhere (I couldn't relocate the thread) of an owner that was getting poor fuel mileage and had diagnostic testing done at the dealer, which revealed the car's timing was off. The user seemed to think the corrected timing had improved his/her mpgs.

 

[GeoBog]

When the engine goes past 10k miles, the mpg gets better. Was skeptical when I first read this but was surprised to see that it is true when I look at my mpg now.

 

[thunderstruck1]

Coasting in gear will improve mileage if the intent is to slow down. If you are in gear and lift off throttle, car cuts off fuel entirely. You are burning 0 gallons per hour when using compression braking. If your intent is to keep going, get car to 5 or 10 over and pop it into neutral and glide. You can bring mileage up that way. Best thing is planning. If I'm coming up to a red light or slow traffic, car is in gear to scrub speed and cut fuel off. If I'm on a long stretch of road between stop lights, I pulse and glide.

 

[Heresy]

Here's my mileage. Yours will get better as the engine loosens up.