Two cars, two questions, please:
230E 92, W124: After I (imprudently) used a valve cleaning product in the
fuel tank, the car starts to lost power specially on hills and hesitates
painfully when accelerating. Sometimes it stalls when idleing. I also
incidentally changed the fuel´s octane for a higher one at the same time.
I dismounted the fuel filter and it was very dirty. I cleaned it as much as
I could and reinstalled it. Car went well for a while, then same deal. I
dismounted again the filter and it was dirty again. The cleaning product
seems to have removed or diluted some kind of tank´s sediment. Is the
solution to change the fuel filter, or I will end up with a new filter
clogged? Which other thing would you suggest to do?
E240 98, W210: During a recent travel I changed the engine oil in a non
dealer shop. The electronic dashboard now shows permanently the "exceeded"
alert and the "tool" figure asking for service. I have tried many times the
procedure listed in the car´s manual to clear the message, but it doesn´t
work. Is there anything else that I can do to reset it?
I will appreciete your suggestions.
Nothing could dissolve something like that. I suspect you just got bad fuel.
The solution is to drain the tank completely and install a new filter.
Reusing old filter is just not worth it as you learned.
You are right as usual. I drained the tank and loaded high octane fuel from
other gas station. The car now works almost normally. Today I will replace
the fuel filter hoping to close the case.
As for the W210 I will try the reset procedure more carefully.
You are right as usual. I drained the remaining half tank of high octane
fuel. Then I load a tank of lower octane fuel from other gas station. The
car began working almost normally. Today I will replace the fuel filter
hoping to close the case.
And the W210´s dashboard now is clean, after I followed the reset procedure
If the car was running fine, why did you do this? If your car runs fine
on low octane fuel, you should save your money and enjoy the increased
power and higher gas mileage that comes with low-octane fuel; putting
high-octane fuel in a car that doesn't need it is, well, a considerable
waste of money and natural resources.
Those parts aren't cleaned during maintenance, they are replaced. Try
replacing it/them and let us know how it goes.
I'm experiencing the same thing, running a vegetable oil mix in my
diesel, since the veggie oil breaks up all of the junk that the
pertroleum diesel left behind. I've just signed up for the fact that I
need to change my fuel filters pretty regularly 'til it's all cleaned up
(like, once every couple of fills). Changing the fuel filters on my car
is easy, if messy, so it's not a big deal.
Have you examined the oil level with the dipstick, and does it read too
Recently the gas station was out of low octane fuel. So I put in half tank
of high octane. I felt the car running and idleing moe smoothly, and in my
ignorance decided to continue using the high octane. It´s just the blind
desire to improve the old car´s performance. I just love this machine, the
W124, it´s inherited from my father. You know, sometimes love makes one do
stupid things. From now on no more high octane, and I orderered a couple of
fuel filters for spare.
Ah ha! "Out of low octane" is the answer! The gas station was pumping out
all the gunks in their tank onto your car. I bet the high octane is also low
when filling up your car and thus pumped all the gunks into your tank. Don't
fill from this gas station anymore.
Years ago I did some experiments at various gas stations, and my results
indicated that for the car I had at the time, the increased price of
"good" gas was more than offset by the better mileage I got on that gas.
The price differential was maybe 5% but I got over 10% more miles on a
gallon, so between the actual less money per mile I also had to go to
stop to fill up slightly less frequently.
As for high-octane fuel, octane is a combustion retardant, so high
octane fuel is harder to ignite in the engine. That may be why it
seemed to run smoother, because it wasn't burning as it usually does.
The rule of thumb is that you should run the lowest octane fuel in your
car as you can without causing the engine to ping.
It´s nice and useful to know your calculations, and I thank you for sharing
the info. Such experiments must have required time and patience.
Regarding the octane, now that I think of it, at the beginning the
engine seemed smoother (good, I thought), but soon the smoothness (and my
restless) was growing to the point of acute lack of power.
It was not only the octane though. I already changed the fuel filter and
broke the old one, the inside roll of paper was full of dirt.
The filter was a few months old, so the fuel shortage at the gas station
sure must have something to do with the it.
Anyway, I learned several lessons with this problem.
As I understand it, the sludge problem in Diesel fuel is fundamentally
different than in gasoline. In gasoline the likely cause is sediment in
the gas station's tanks. However, current Diesel fuels are both
chemically and bacteriologically instable -- tending to break down into
a black sludge, Asphaltene. To cure sludge in Diesel, you need a
product like Bio-Con or Algae-X which serve three functions: dissolving
condensed water that settles in the bottom of a tank so that it can be
burned, killing the microbes that feed on Diesel causing it to break
down, and dissolving the sludge into the Diesel so it can pass the
filters and be burned.
In major cases the solution requires that the fuel tank be removed and
steam cleaned. A less severe case might be solved just by chemical
treatment. I am coping with this on my 1977 300D (320,000 miles) right
now and attempting the chemical cure. Also, be sure to keep spare
prefilters on hand and change them when a power loss becomes evident.
It also helps not to run the tank below half-full.
I'd be interested in any other comments others can provide.
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