'01 E430 4matic bad fuel economy, please advice
Thread Starter
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Joined: Oct 2011
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2014 S550 4matic
'01 E430 4matic bad fuel economy, please advice
Hi everybody, I've just bough a 01 e430 4matic w/106kmi. The car was passed emission recently, running excellent, but don't know why the fuel economy is so bad: around 10mpg!
Its tires is new, thread is about 90% remaining
I had a 1999 e430 rwd before, that car I used for a 10 years and at 125kmi. it s still on 19 mpg!
So anyone has an idea? Please help! I am trying to use a bottle of fuel injector cleaner, like I had done before to my old E430 RWD, but I doubt it s not a corrected move??
Thanks in advance
Its tires is new, thread is about 90% remaining
I had a 1999 e430 rwd before, that car I used for a 10 years and at 125kmi. it s still on 19 mpg!
So anyone has an idea? Please help! I am trying to use a bottle of fuel injector cleaner, like I had done before to my old E430 RWD, but I doubt it s not a corrected move??
Thanks in advance
MBWorld Fanatic!
Joined: Oct 2007
Posts: 1,564
Likes: 19
From: SoCal
98 Brilliant Silver E320 Wagon
If it passed the smog test chances are that the plugs are okay.
So it points to something happening while the car is moving since the smog test is stationary. Check the brake system (including the parking brake) for dragging. Also, bad alignment can cause low mileage but you'd see it in tire wear if it was bad enough to cut the mileage almost in half.
Another possibility is a gas leak. Another is a speedometer error. If you are near a freeway you can check speedo using mile markers.
I assume you are calculating the gas mileage not using the instrument cluster readout. If not, do the calculation.
So it points to something happening while the car is moving since the smog test is stationary. Check the brake system (including the parking brake) for dragging. Also, bad alignment can cause low mileage but you'd see it in tire wear if it was bad enough to cut the mileage almost in half.
Another possibility is a gas leak. Another is a speedometer error. If you are near a freeway you can check speedo using mile markers.
I assume you are calculating the gas mileage not using the instrument cluster readout. If not, do the calculation.
Last edited by RichardM98; Nov 1, 2011 at 03:48 PM.
Thread Starter
Newbie
Joined: Oct 2011
Posts: 9
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2014 S550 4matic
If it passed the smog test chances are that the plugs are okay.
So it points to something happening while the car is moving since the smog test is stationary. Check the brake system (including the parking brake) for dragging. Also, bad alignment can cause low mileage but you'd see it in tire wear if it was bad enough to cut the mileage almost in half.
Another possibility is a gas leak. Another is a speedometer error. If you are near a freeway you can check speedo using mile markers.
I assume you are calculating the gas mileage not using the instrument cluster readout. If not, do the calculation.
So it points to something happening while the car is moving since the smog test is stationary. Check the brake system (including the parking brake) for dragging. Also, bad alignment can cause low mileage but you'd see it in tire wear if it was bad enough to cut the mileage almost in half.
Another possibility is a gas leak. Another is a speedometer error. If you are near a freeway you can check speedo using mile markers.
I assume you are calculating the gas mileage not using the instrument cluster readout. If not, do the calculation.
about the leaking of gas tank or somewhere inside the car , I dont know how to check it out, and there is no gas smell to be noticed
I have just put in a bottle of an fuel injector cleaner, lets see the result later
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Joined: Jan 2007
Posts: 484
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From: Südflorida
'99 E430, '05 ML500, '15 GLK350
Easy method for calculating real gas mileage (assuming plenty of gas stations nearby):
wait till reserve light comes on, then head to nearest gas station
get 10 gallons of gas, reset odometer to 0
drive until reserve light comes on
divide odometer reading by 10
easy to adjust for any extra miles driven between light on and getting gas.
if you do this all the time, you also have a reliable number to let you know if something is amiss (or if you've been driving too fast).
wait till reserve light comes on, then head to nearest gas station
get 10 gallons of gas, reset odometer to 0
drive until reserve light comes on
divide odometer reading by 10
easy to adjust for any extra miles driven between light on and getting gas.
if you do this all the time, you also have a reliable number to let you know if something is amiss (or if you've been driving too fast).
Thread Starter
Newbie
Joined: Oct 2011
Posts: 9
Likes: 0
2014 S550 4matic
Easy method for calculating real gas mileage (assuming plenty of gas stations nearby):
wait till reserve light comes on, then head to nearest gas station
get 10 gallons of gas, reset odometer to 0
drive until reserve light comes on
divide odometer reading by 10
easy to adjust for any extra miles driven between light on and getting gas.
if you do this all the time, you also have a reliable number to let you know if something is amiss (or if you've been driving too fast).
wait till reserve light comes on, then head to nearest gas station
get 10 gallons of gas, reset odometer to 0
drive until reserve light comes on
divide odometer reading by 10
easy to adjust for any extra miles driven between light on and getting gas.
if you do this all the time, you also have a reliable number to let you know if something is amiss (or if you've been driving too fast).
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From: Socal, Chino
E55 2006 / CLS55 / S450 / Jag XKR2011
Change the plugs/wires, tranny oil flush, engine oil flush, fuel system cleaner Techron and very important Air filter. Also don't forget the differential oil change in this case.
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Senior Member
Joined: Jan 2007
Posts: 484
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From: Südflorida
'99 E430, '05 ML500, '15 GLK350
If you're getting half the mileage of your other one and can't find any obvious culprits (like the rolling resistance is infinite) then my suspicion would be clogged cats, although I would have to think you'd be getting some codes by now.
What state are you in? Does the smog check include an OBD2 hookup, or just a sniffer?
What state are you in? Does the smog check include an OBD2 hookup, or just a sniffer?
