Just quit

Maintenance/Repairs
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1

while on way to parts store car started acting like it was running out of gas. A half block from gas station it quit . I walked to station got gas put in the tank the engine would crank but would not start. I got towed home and still will not start. It will crank but thats it. Any ideas ? 3.0 L inline 6 300 E

2

What year model is the car?

Odds are this is a CIS injection car and doing a diagnosis can get a bit sticky; especially if you’re not familiar with CIS and you do not have the specialized CIS fuel pressure tester.

Get a can of aerosol carburetor cleaner and spray a healthy shot into the intake. If the engine will start and run for a few seconds this will at least point you towards a fuel delivery problem.

A fuel pump failure would not be uncommon because those CIS pumps run at much higher than normal fuel pressure as compared to a normal FI system and pump failures can be intermittent or just dying suddenly and staying that way.

If the engine does not start with the shot of carb cleaner you then need to check for a spark at the plugs.
Sorry I can’t be specific but there’s just not enough info known that will allow me to get into the general vicinity of the problem area.

3

Thanks! The vehicle is a “91” Benz 300 E 3.0 L inline 6 cyl. automatic

4

Also this series as dual exterior fuel pumps mounted under vehile along with fuel filter. The filter has been changed.

5

There is no way for me to be able to make much of a guess without knowing if the engine does not have a spark or if it’s a matter of no fuel pressure.
The first step is to shoot some carb cleaner into the intake as I mentioned and see if the engine will start and run for a second or so. If it does run then you know it’s a lack of fuel pressure issue more than likely.

To go into that requires a specialized pressure tester. Given the age of the car and if the fuel pump has never been changed, a wild guess might be a failed fuel pump because those things do take a serious beating over time. Usually the impeller bushing and commutator wear out in them.

I’m no Benz expert but am familiar with CIS. Are you sure that car has dual pumps? The thing by the fuel pump that looks like a pump is probably a fuel accumulator; not a pump.

6

Thanks for the input . I have been out of town and unable to work on the car. I will give this a try and let you know the out come. Thanks again h p j