Mileage - fuel leak?
- Thread starter anthony
- Start date
MMercury
Well-Known Member
- Messages
- 481
- Reaction score
- 5
Would it really matter if you got great mileage and still had a bad smell?
Details about your vehicle might help.
Euro or North American model? Maintenance of fuel lines and hoses? Age? Loose clamps? Gas tank sender seal? Trunk seal? Look for obvious leakage at any point on the fuel trail: stem to stern. Could be an ill fitting fuel filler, problem at the tank, or even leaky lines at the carbs. Carbs with loose fittings or stuck floats? Disconnected carbon canister fuel vapor/vent lines?
See also: http://www.e9coupe.com/tech/gas_smell.htm
and: http://www.e9coupe.com/forum/showthread.php?t=1313
Search the archives and you will find a variety of gas mileage reports. 15-25 mpg. Tire pressure, engine/vehicle condition, typical terrain, air conditioning, axle ratio, driving style, and riding the brakes can all add up to: "Your mileage may vary."
Last edited:
JhwShark
Well-Known Member
I can only suggest a couple of things to check:
Stick your finger in the tailpipe, is it coated with black soot/carbon -- if so, could be running Rich.
Have you measured CO output at the tailpipe -- could help confirm Rich
As suggested check the fuel lines for cracks -- old hoses degrade
Have you ever rebuilt the Z's -- sometimes the pump diaphram in the carb gets weak or the spring does (though less on the spring)
Has anyone done a tune up where they messed with the A/F (mixture screw -- this could lead to Rich
Bad old high milage spark plugs -- could be fouled causing more fuel to be burnt
Valves not been adjusted for way too long --
These or a combination could ad up to bad milage.
Jon
Stick your finger in the tailpipe, is it coated with black soot/carbon -- if so, could be running Rich.
Have you measured CO output at the tailpipe -- could help confirm Rich
As suggested check the fuel lines for cracks -- old hoses degrade
Have you ever rebuilt the Z's -- sometimes the pump diaphram in the carb gets weak or the spring does (though less on the spring)
Has anyone done a tune up where they messed with the A/F (mixture screw -- this could lead to Rich
Bad old high milage spark plugs -- could be fouled causing more fuel to be burnt
Valves not been adjusted for way too long --
These or a combination could ad up to bad milage.
Jon
I had both, Gas smell and poor mileage, On further investigation turned out to be a hole (holes) in the tank from rust.
I pulled the tank and had it dip striped, it came back not looking very nice!! several more pin holes and the seam where the two halves join was in a bad way in a few places, about $200 later with the panel beater and treated internally with POR15 gas tank paint its looking great.
I would advise anyone who has the gas smell in the trunk to at least pull the tank and have a real close look for rust and holes, I thought mine wasn't to bad until I got it back from the striper, this cleans it up inside and out and takes away anything covering up any rust present, I went a little further by prising open the joining seam slightly with a chisel before it was striped as this is the prime spot where the trouble starts, after it was all fixed I treated between the two halves of seam with the correct anti rust paints and crimped the seam back together, painted the outside (bottom half with rubberized anti stone chip sill/rocker paint), job done.
I pulled the tank and had it dip striped, it came back not looking very nice!! several more pin holes and the seam where the two halves join was in a bad way in a few places, about $200 later with the panel beater and treated internally with POR15 gas tank paint its looking great.
I would advise anyone who has the gas smell in the trunk to at least pull the tank and have a real close look for rust and holes, I thought mine wasn't to bad until I got it back from the striper, this cleans it up inside and out and takes away anything covering up any rust present, I went a little further by prising open the joining seam slightly with a chisel before it was striped as this is the prime spot where the trouble starts, after it was all fixed I treated between the two halves of seam with the correct anti rust paints and crimped the seam back together, painted the outside (bottom half with rubberized anti stone chip sill/rocker paint), job done.
pmansson
Well-Known Member
One of my original 3,0 CSi cars does 22 MPG (US gallons) at 70-90 MPH on the Autobahn.
The 3,5 engines will do far? less.
The 3,5 engines will do far? less.