Hi folks I have a 1993 300e 2.8 engine with 160,000 miles. I am new to this site (my first post) and I need you help.
I just got the head gasket leak fixed that has been leaking for 4 years and was getting out of hand, what prompted me to get the gasket fixed was the unrelated problem(?)that came out of the blue one day that was subsequently diagnosed as a vaccum leak. The vaccum leak limited the car to a top speed of 20 mph and 2000 rpms (it would hit 2000 rpm and cut out) provided I kept rapidly tapping the gas pedal to keep it from stalling out right.
In addition to the head gasket I had to get the engine electrical harness, fuel pump relay,over voltage relay,booster hose,air mass meter,radiator(4 years of oil in it), level senser,spark plugs,air filter,belt tenser. oil ,coolant brakes and rotors and some other stuff for $3,600 and my first born.
The car now runs great EXCEPT when at idel 600rpms to 800 rpms the car misses. The missing cylinders vary and there is no pattern to it. the missing at least for now does not cause the car to stall in fact it hardley registers on the tach, its like the car hiccups. However above 1000 RPM the missing disappears! the MB Tech rechecked the electrical harness, mass air sensor, plugs and ignition cables,the compression is right on in all cylinders, he said there are slight fuel injector leaks but he felt they were of no consequence, also all parts he put on the car were original MB parts.
He was shaking the crank shaft sensor and that caused his electrical testing devise to register diffrent readings from it. He said by shaking it by the batttery it creats a magnetic field,cool but it did not help resolve the problem.Since I needed the car to take a 500 mile trip his efforts to find the cause and the rest of my money are postponed for now. the car ran great on the highway during my trip but the missing continues at idel no better or worse.
HELP What do you think it is???What should he check next ?? Also is there away to increase the RPMs to900 or 1000 and get rid of the problem this way? Is that asking for trouble?Can I continue to drive the car with this problem or am I going to cause a bigger problem if I do this ? MY tech also mentioned that the motor mounts are worn would this have any bearing on the problem? I imagine if I got the mounts replaced I would not feel the miss in the car which I do now.
Your ideas are appreciated, I need to keep this car for another 40,000 miles.
Thank you
Scott
I just got the head gasket leak fixed that has been leaking for 4 years and was getting out of hand, what prompted me to get the gasket fixed was the unrelated problem(?)that came out of the blue one day that was subsequently diagnosed as a vaccum leak. The vaccum leak limited the car to a top speed of 20 mph and 2000 rpms (it would hit 2000 rpm and cut out) provided I kept rapidly tapping the gas pedal to keep it from stalling out right.
In addition to the head gasket I had to get the engine electrical harness, fuel pump relay,over voltage relay,booster hose,air mass meter,radiator(4 years of oil in it), level senser,spark plugs,air filter,belt tenser. oil ,coolant brakes and rotors and some other stuff for $3,600 and my first born.
The car now runs great EXCEPT when at idel 600rpms to 800 rpms the car misses. The missing cylinders vary and there is no pattern to it. the missing at least for now does not cause the car to stall in fact it hardley registers on the tach, its like the car hiccups. However above 1000 RPM the missing disappears! the MB Tech rechecked the electrical harness, mass air sensor, plugs and ignition cables,the compression is right on in all cylinders, he said there are slight fuel injector leaks but he felt they were of no consequence, also all parts he put on the car were original MB parts.
He was shaking the crank shaft sensor and that caused his electrical testing devise to register diffrent readings from it. He said by shaking it by the batttery it creats a magnetic field,cool but it did not help resolve the problem.Since I needed the car to take a 500 mile trip his efforts to find the cause and the rest of my money are postponed for now. the car ran great on the highway during my trip but the missing continues at idel no better or worse.
HELP What do you think it is???What should he check next ?? Also is there away to increase the RPMs to900 or 1000 and get rid of the problem this way? Is that asking for trouble?Can I continue to drive the car with this problem or am I going to cause a bigger problem if I do this ? MY tech also mentioned that the motor mounts are worn would this have any bearing on the problem? I imagine if I got the mounts replaced I would not feel the miss in the car which I do now.
Your ideas are appreciated, I need to keep this car for another 40,000 miles.
Thank you
Scott
