Fuel Mileage Sucks on '94 325 Convertable

I don't know about the 4-doors, never had one, but I have a 1996 328 5-speed convertible, it gets better mileage. On road trips at 60-65mph, it averages close to 30mpg, round about town about 23 to 25. The car would be heavier than a non-convertible, there would be a little more wind drag from the soft top. I must say that I also have the removable hardtop for my car, and find little difference in gas mileage when it is on (although the car would weigh another hundred pounds or so). The above figures of mileage are for conservative driving (not as conservative as possible, but changing gears at about 2300 to 2600 rpm. Mileage drops below 20 with spirited driving. Having the air conditioner running makes maybe 1mpg difference. Jim

Could be the O2 sensor? Could also be the increased weight of the convertible. Yep, that's right, the added frame below, designed to improve the chassis stiffness, is heavier than the missing roof above.

You are correct. 325Ci would be a coupe. 325iC is a convertible.

325CiC is sometimes used to denote a 2 door convertible, but it's redundant since there are no 4 door BMW convertibles.

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-Fred W

No, at least not here in the US. The S in 325iS was used in the past to denote a 2 door (coupe), with or without the Sport package, but this has now been replaced with the leading C as in 325Ci. 4 doors are always called 325i whether they have the sport package or not.

-Fred W

What about final drive ratios? Are they the same? Just a thought...

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-Fred W

Can't you people read! ;-)

It's a Ci, irrespective of it being a coupe or convertible. If you still don't believe me go here :

or here : And I've already posted the OFFICIAL BMW mpg stats for coupes v convertibles v saloons, and it show convertibles use more fuel! Your car is fine, there are no faults, it's just heavier.

The Sticker Price hasn't changed much in 12 years, my car has the original window sticker, and the price in 1994 was pushing $42,000 (USD).

or here :

According to Bentley, the trans and final drive are the same.

I think the consensus is that the rag top weighs more, and thus sucks up more gas.

After getting over the thrill of having the wind whistling across my massive expanse of a forehead -- it extends most of the way to my shoulders these days -- I find that I am getting pretty close to 24mpg, whereas my old car was giving 25mpg. I haven't left the top up long enough to find out if aerodynamics is part of my fuel loss, but I'm pretty sure the weight is my most significant issue.

I was hoping you guys would come up with a more temporary cause of my low mileage -- something along the lines of the O2 sensor causing it to run rich -- that I could fix, but it turns out the rag top is hauling around extra baggage that eats into the gas tank.

I once read that as rule of thumb every 100 kg in the boot add about 1 litre per 100 km fuel (whatever that is in gallons per mile).

0.26 US gal per 62 miles...you work it out from here...

DAS

For direct contact replace nospam with schmetterling

On Wed, 24 Aug 2005 11:26:17 -0700, "J Strickland" waffled on about something:

The weight of the car won't help it, but having the top down gives you the aerodynamics of a sale boat side on!

All that wind and buffeting you hear with the roof down is turbulence, turbulence is bad... It resists your smooth passage through the air.

Over here in the UK they even try to encourage people to remove their roof racks when they don't need them because of the increased fuel consumption.

Dodgy.