Gas Miles per Gallon tracking

[fun42]

Its starting to get cold out and our mileage is way done. Does using the heater or having the heated seats on impact the mileage? I wouldn't think so but I'm looking for an explanation. We have averaged 38 to 42 for the last couple of months, but our last two tanks have been 32 and 31. Tire pressure is fine, no real different drive pattern. Always use 93 octane. Have about 6000 miles on coupe. Great gas prices today - $2.41 for 93. Any ideas for what's up with the drop in mileage?

[sprale]

Originally Posted by fun42

... but our last two tanks have been 32 and 31...
...Any ideas for what's up with the drop in mileage?

I have been a big fan of the Smart since its inception. I was able to convince a UK dealer to send me brochures shortly after the initial public sales, to my home here in the States. I always have been a microcar fan, and the Smart is right in line with my needs, but not my expectations.

If the diesel were imported here, I would already have one. The Toyota Yaris is looking at around 39/44 average in the real world, on petrol. The Smart seems to be falling a bit short, on petrol of course. The new Jetta TDI is managing 42/48, in a wagon!

Until then, my 250 Kawasaki Ninja will do for a commuter. It returns around 75mpg on average in urban commuting, at about $3k retail new ('07 model).

[jimvw57]

Using the heater or the heated seats should have no effect on gas mileage. however, starting a car in a colder temperature will. The choke or throttle enrichner circuit will use more gas when starting and since it takes a little longer to warm up, mileage will drop. Even keeping it in a heated garage won't make much difference once you get outside, it's still cold out.

I have experienced lower mileage when there is a strong wind.

[xcrew229x]

7.3 gallons 288 miles 39.45 mpg all around town on 87 octane regular. Yea I'm happy.

[loplop]

Here is my mileage calendar. Driving in Los Angeles, all City, always single person, no cargo, not hot footing, these are the results:

05-03-08 179 8.000 22.375
06-09-08 188.5 7.550 24.066
06-17-08 165.2 7.660 22.454
06-25-08 185 23.23

07-05-08 158 7.385 21.40 10.99 1,813
07-11-08 162 7.865 21.08 11.16 1,975
07-20-08 164.8 7.727 21.33 11.03 2,140
07-30-08 156.1 7.377 21.16 11.11 2,297
picked up from Mercedes 08-16-08 full tank
08-23-08 148.8 7.480 19.893 14.20 2630

I took it to Mercedes, they tested and drove for appr. 40 miles and came up with 27 mpg.

I even had my wife drive it, results are the same. I will keep on checking and posting results.
Any suggestions?

[Harleytoys]

I just went to Tucson & back from Reno, just under 2,000 mile trip with city/hwy & all kinds of driving. Did the math & came up w/38 mpg average overall.

[prm1177]

Originally Posted by sprale

I always have been a microcar fan, and the Smart is right in line with my needs, but not my expectations.

The Smart seems to be falling a bit short, on petrol of course.

My fill-up last night gave me a calculated mileage of 47.8 MPG. My passion now has 13,400 miles on it, and my commute (30 miles each way) has 1/3 suburban roads (with many stoplights), 1/3 freeway, and 1/3 mountain roads. The Smart can deliver high mileage, but as with any very small engine, how you drive it can have a greater impact than with a bigger power plant. My tracking data on Fuel Economy show my average over the past 10 months to be 46.8 mpg. Not bad.

[Harleytoys]

I drive it like I stole it - and the cops are chasing me - and I have a felony warrant!

[GHammerly]

Originally Posted by loplop

Here is my mileage calendar. Driving in Los Angeles, all City, always single person, no cargo, not hot footing, these are the results:

05-03-08 179 8.000 22.375
06-09-08 188.5 7.550 24.066
06-17-08 165.2 7.660 22.454
06-25-08 185 23.23

07-05-08 158 7.385 21.40 10.99 1,813
07-11-08 162 7.865 21.08 11.16 1,975
07-20-08 164.8 7.727 21.33 11.03 2,140
07-30-08 156.1 7.377 21.16 11.11 2,297
picked up from Mercedes 08-16-08 full tank
08-23-08 148.8 7.480 19.893 14.20 2630

I took it to Mercedes, they tested and drove for appr. 40 miles and came up with 27 mpg.

I even had my wife drive it, results are the same. I will keep on checking and posting results.
Any suggestions?

They should check tail pipe emmisions, with that mileage it should be horrible. They i'm not a car mechanic but a plugged up exhaust system or catalitic converter could do this, also a clooged up air filter, defective fuel pressure regulator, defective fuel injectors, bad oxigen sensors or spark plugs and ignition coil packs.
First thing I would look at is the condition of the spark plugs mostly to see if it's running ritch on all 3 cylinders or only ritch on one or two.
If all are ritch most likely the oxigen sensor/s are bad.

[kenarmstrong]

For the past several tanks, I've consistenly averaged 500 kilometers (312 miles) per tank using slightly over 29 litres per fill for an average of 39 mpg - total city driving.