What should be checked if water was put into the gas tank.


Asked by Aug 24, 2013 at 07:42 PM about the 1989 Mercedes-Benz 420-Class 420SEL Sedan

Question type: Maintenance & Repair

After adding gas I decided to syphon the gas and put new gas in the tank.  It started a
few times but wore down the battery. Meanwhile, I changed the spark plugs, got a new
fuel filter, then someone messed with the fuel pressure regulator. After that I bought a
new fuel pump, but someone said the two I had were fine, so the fuel pump was
returned..The car still won't start, but almost. Next  the fuel injectors were mentioned.
What do you suggest I do?  An anylast, will make the final decision.,, but I want to see
the car start and drive it to the mercedes benz mechanic.,So how can I get the car to

8 Answers


if you are going to take it to the Mercedes mechanic, don't waste your money buying parts that may or may not work. you would be better off just having it towed.

2 of 2 people found this helpful.

Fuel injection systems don't like water if it has reached your injectors you are in for a fight getting them to finally purge out the water. If you can locate the return line try putting it in a can and cycle the fuel pump until all you get is pure fuel, reconnect it then try to start it, may take a number of tries to get the injectors purged.

2 of 2 people found this helpful.

you could run a few cans of "HEET" with your current tankful of octane 93 (with techroline)~ if it still runs, would take this course~

1 of 1 people found this helpful.

Does it crank? Will it choke trying to start up? Have you tried spraying some carb cleaner in the intake?

2 of 2 people found this helpful.

It does turn over, yes. and over and over. I wore out my battery. With starting fluid it does start, then dies. Should I try carb cleaner instead of starting fluid?

1 of 1 people found this helpful.

does the fuel pump work?....in other words when you turn the ignition to the "on" position, do you hear the fuel circulating thru the fuel rail?

1 of 1 people found this helpful.

check for the presence of 12 volts at the fuel pump~

1 of 1 people found this helpful.

Sounds like a Mercedes dealer is waiting for your call.....there is no way to even guess what's going on here.

2 of 2 people found this helpful.

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