Fuel Starvation Problem? - PeachParts Mercedes-Benz Forum

Apodman · #1 09-09-2004, 10:05 AM

In the residue of Hurricane Francis, my 280E quit on me 200 yards from home as I started to work today.

For the last month or so, with only occasional drives, the M110 engine would start as though it was running on 3,4, or 5 cylinders, in other words roughly. It would smooth out in a minute or so and all was well. Took it to the hardward store on Saturday, a did an Italian tune up on the way: a couple of kick downs and holding it in third gear a bit. Again, all was well.

This morning in the pouring rain, it started roughly, smoothed out and I was on my way. It started running roughly again, then died. The engine cranks and fires, but does not continue to run. I don't think the rain has anything to do with it.

Not quite two years ago, I replaced the fuel pump with a new Bosch. Prior to its failure, it was making excessive mechanical noise. Not the case currently. I have also replaced the fuel accumulator and fuel filter in the last 6 months.

It seems to me that there is some kind of fuel starvation problem. Could I already need a new fuel pump? Does a sending unit relate to fuel delivery? I did put in new injectors a month ago, but I don't see a possible connection to that project.

Any thoughts or suggestions?

Thanks in advance, Alex

230/8 · #2 09-09-2004, 10:36 AM

If you car was exposed to strong wind and rain from the hurricane, then I would make sure everything is truly dry under the hood, check the distributor for any small amounts of water, and then add a couple of bottles of gas dryer (it's just alcohol) to the tank and refill it with fresh gas. Go to a trusted station for the gas or they may have some water in their big tanks. I'd rule out these easy and simple things first before assuming some other mechanical gremlin was at fault.

Just a thought...

230/8

Apodman · #3 09-09-2004, 03:50 PM

Does anyone know if this engine (1978 M110 w/ K-Jetronic injection) has a MAS relay?

300SDog · #4 09-09-2004, 11:00 PM

If it was me, I'd raise the hood vertical, an excellent feature of the 123, and park the car with the engine bay facing direct sunlight to dry out for several hours. And dont be in such a hurry to hack away at complicated relay networks that nobody can completely understand.

psfred · #5 09-09-2004, 11:46 PM

fuel pump relay, fuel pump, tank screen, not necessarily in that order.

Water in the fuel will drive you nuts, but I'd not add water remover myself, I'd drain the tank instead. Use the water remover AFTER you get all the water out of the tank.

You MUST get the water out of the fuel distributor pronto if you have any in there, else it will rust away and fail, very expensive these days.

Make sure the ignition module is OK, the wires are OK, and the cap and rotor new and sealing -- condesation causes carbon tracking, and failed cap and rotor.

Peter

Apodman · #6 09-10-2004, 08:38 AM

Thanks for the above advice. I'll dry her out this weekend. Though I am not convinced that it is either an ignition problem or a water problem, given its readiness to fire initially, then stumble and stall.

Peter, do you know where I can find the fuel pump relay, so I can check it for cracked wires or poor connection? Any recommendations for how to test a fuel pump? Unfortunately, I have a full tank of gas, so draining it and checking the screen are, for the moment, lower on my list than other possibilities.

Thanks, Alex