My wife's E320 has an 18.5 gallon tank, plus a 2,,5 gallon reserve.....If you fill it up, it will burn around 11 gallons and then the engine reacts as if it were about to run out of gas. Refill the gas tank and the car runs flawlessly until it burns off another 11 gallons......your thoughts?

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Currently Driving
2006 E320 CDI
1999 E300 Turbo Diesl
2002 ML500
1995 E320 Station Wagon


MBs I've owned
1997 E320 Assassinated by Pine Tree
1987 300E Wife Killed Engine
1981 300D Stretch Limo Total Loss
1970 250 Coupe 212,000 mi.
1974 450sel 184,000 mi.
1974 240D 377,000 mi.
1977 300D 204, 000 mi.
1979 280se God Only Knows!
1983 240D 130,000 mi.
1972 220D 280,000 mi.
1983 300SD 244,000 mi.

This just happened to me; short story is your gas tank collapsed.I have the same car w/ 206k miles. Recently very cold in New York (may, or may not have had anything to do with this). Suddenly one day recently, the gas gauge started going crazy, yellow reserve light was on, needle was bouncing all over the place (assume tank was collapsing under vacuum at this point, hampering sender unit). Not knowing if I had gas or not, i filled up. WHOOSH, big vacuum sound when I opened the tank cap. WTF? Filled up w/ only 5 gallons. WTF? Used the car for another day, and then it died on me, on the approach to the tappan Zee bridge! Knowing I had just filled up, never thinking could be out of gas, I had it flat-bedded of the bridge to the dealer. Dealer says "You are out of gas. We put one galloon in, and it runs". WTF? I took the car to a station, and put another 5 gallons in, filled it right up. Tank only holds less than seven gallons now. Diagnosis is that something failed (vent or purge valve), fuel pump pulled a vacuum, tank collapsed, fuel guage creamed. Car runs great, but sputters out of gas at 80 miles! I know it is time to refuel when she stats to sputtering after a hard turn.

a member had this problem, and I beleive once all lines were plugged - he used an air compressor to pop in back.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

It must have been quite a sight!!! I have a relative whose car broke down INSIDE some tunnel in Maryland (Ft. McHenry tunnel?). The cop had to use his car to push the car through.

Imagine all the mean looks!

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Ben
1987 190d 2.5Turbo

I actually lucked out. Coasting w/ idle power, the bridge(with no shoulders) lay ahead. Just at the last moment, I popped to the right and landed on a small triangle of land formed by the on-ramp from the state police barracks. They were on it immediately, called a flatbed,and wisked me away. Could have been deadly.

Replace the vent to the gas tank? An experiment- when the engine starts to "act funny", open up the gas cap, hear the whoosh, and then drive around some more. Engine acting normally = replace tank vent.

Check the fuel pumps- the TE has two. If only one is functioning normally, you will experience issues at less than half a tank. Replace both, not just one at a time, if you do not have records of their past replacement.

Check the rear rubber fuel line between the tank and the rear most fuel pump. That hose has a bend, and it can collapse or crack (drawing air into the system forward).

And of course you replace the fuel filter every 30K, so that is not an issue, right?

I would put "collapsed tank" as the last thing to check.

First,the fuel tank capacity of the W124 wagon (as well as the W210 wagon) is approximately 18.4 gal including a 2.5 gal reserve. Check the tank for damage by inspecting the tank from under the car. It is very easy to bottom out the rear of the car, compressing the floor of the tank. IIRC the fuel pickup is conveniently located where the tank gets damaged. The PO of my 300TE wagon damaged the tank in this fashion which reduced the usable capacity of the tank to 16 1/2 gallons or so. Mark

Whassup?