fuel consumption help?????

[hitman3]

hi guys

does any one have a chart of fuel consumption of 1978 928 Porsche i been filling this car nearly every second day with full tank it is with auto gear it is doing now about 4-5 km a liter it does not sound right any idea what is wrong?

[JhwShark]

4-5 km/l sounds bad...sorry do not have any charts or manuals.
check to see if you have a leak after the fuel pump while running as well as trace the line from tank to engine
check your timming
check your plugs: fouled and larger gap

[MPDano]

How does the exhaust smell? Does it smell really rich? Your CIS and your adjustment will be a long 3mm allen wrench. Also a very large screw in the general vicinity.

[hitman3]

well did it all change the fuel filter change all hoses from and around the tank new spark plags (by the way what should be the gap on the plags)change all vacume lines in the midle of clening the injectors changing the rubber sills clining the inteak manifold changing the rubber conectors on the manifold and so on and on and on///////////

[hitman3]

Originally Posted by MPDano

How does the exhaust smell? Does it smell really rich? Your CIS and your adjustment will be a long 3mm allen wrench. Also a very large screw in the general vicinity.

it smell ok i have conected the car to a computer and it show that all if fine still its a blood sucker

[Rixter]

early cars get horrible gas mileage, 13-15 mpg or so about town, so you're a little below that, but not too bad, I'd suspect a slight rich issue, how did the old plugs look? did it sit a while?

[Normy]

My '85 S2 gets around 11 mpg around town. That works out to about 21 liters/100km.

-If you drive primarily in town, your fuel consumption will go through the roof. A car engine needs an enormous amount of fuel to accelerate to 100 km; staying there takes only about 20% of the fuel it takes to get there!

Listen, these are BIG engines. This car was designed for one purpose: fast transportation. The large engine can handle the heat of continuous 250 km/hr driving, but you pay for that large engine whenever you are driving through a town. I typically use 21 liters of fuel for every 100 km here in south Florida. On the interstate highway, it goes down and I can approach 11 liters/100 km, or about 21 miles per gallon. I rarely drive on the the interstate, so I pour gas into this car. Of course, though I drive it most days....it only sees about 2500 miles per year.

Listen- if it is using this amount of fuel...I would do a good tune-up on it and leave it at that. If it is using more fuel than my 310 hp S2....then something is wrong and you need to start looking. If your car smells like an old truck at stop lights...that is a sure sign that you are running WAY rich.

Good luck!

N!

[Arizona_928]

Originally Posted by Normy

If it is using more fuel than my 310 hp S2....

A little off topic, but is yours a euro?

[Normy]

Originally Posted by AZ_porschekid

A little off topic, but is yours a euro?

[I hate that term: "Euro"]

Yes. The car was purchased from a Porsche dealer in Vienna, Austria in June 1985, and imported to Miami. It was federalized ["molested"] in Florida, and has been here ever since. It's first owner committed suicide in the car. I'm the fourth owner.

The ROW or "rest of world" cars sold in England from '84 to '86 were known as 928S2, and I creatively use this moniker for my Austrian version. They have the same fuel injection and ignition as the '85 and '86 32 valve 5.0 liter cars, but have two-valve heads and 4.7 liters. FAR higher horsepower, especially with a good exhaust, due to the wild cams and lack of emissions compromises such as catalytic converters.

There is no reason for this car to use more fuel than the typical '82-'84 L-jetronic US model 928 unless the owner has his foot too the floor too often. Guilty as charged, officer-

[hitman3]

Originally Posted by AZ_porschekid

A little off topic, but is yours a euro?

yes i got it from germany

[MPDano]

Pics are worth a thousand words.