Car sputters and dies when accelerator pushed.
Asked by James Jun 12, 2012 at 04:21 PM about the 1981 Mercedes-Benz 280
Question type: Maintenance & Repair
81 280e sputters and dies when accelerator is pushed. I just replaced fuel pump and filter thinking this was the
problem but it continues to occur. Any ideas before I drop more money.
2 Answers
In 1981 this car should have an oxygen sensor,the o2 sensor controls what is called a frequency valve which bleeds pressures from the lower to the upper chambers on the fuel distributor,this is constantly leaning and richening the mixtures for the best running.This is controlled by a relay possibly labeled an oxygen sensor power supply relay,poor grounds can keep the valve from functioning properly.The biggest issue with the old Bosch K jetronic systems was contaminated fuel( rust ) which will get very expensive very quickly .If the fuel system has been compromised by water you basically need to start at the fuel tank and replace every single component that has had fuel in it,this was one of the downfalls of this injection system.You have to have a supply of good fresh CLEAN fuel,there is a device called a warmup regulator that is about the size of a bar of soap this will have two fuel lines on the top of it and a couple of vacuum lines as well as one electrical plug.one of these lines has a screen inside of it that is inside the holes in the warmup regulator,if the screen is plugged with contaminates stop and check your bank account because it's going to get expensive,you need to find a shop that specializes in older Benzes ,as this is a tricky system to fix if you are not familiar with it,lots of little tricks to make it run sweet.
I got an o2 sensor but am not sure where its located on engine. Is it on the left top of the engine from the front or on the exhaust pipe on the bottom of the engine. I found what looks like the new one they gave me at the parts store but its rusted on and I'm having trouble getting it off so before I go any further with it I want to make sure. I can't find any pics or diagrams on line showing its location. I can't find any vacuum leaks and don't have any testing equipment nor the money right now for a shop after dropping so much already. I do think its the o2 sensor though.