elle

my car has @ 75,000 miles. It starts difficult,runs very rough for the first 5 min. all the lights blink. you cannot try to give it any throttle because it will hesitate or stall. the vacuum gage does not work. Put it in gear go one block and it runs good but not quite right.drive it down road punch it full throttle,goes like a bandit. vacuum gage still not working. drive it a while and if the vacuum gage all of a sudden starts to work the car immediately responds and runs better,but then 2-5 min.later the vacuum gage stops working and car runs worse . Mercedes mechanic replaced spark plugs,distributor caps ,took it home ran the same. brought it back because of lack of use from sitting injectors were sticking. advised adding fuel injector cleaner along with the gas which we have done for the last 400 miles. The problem is the same ????. Any advice will be highly appreciated.
The car is in mint condition,one owner,love it except for this issue.

MJ50

moved to R129 forum...

sutliffe

Have you looked into the Camshaft Position/Reference Mark Sensor and or the crankshaft position senor? Sounds like one or both of these needs replacing. This may be one of several problems you have with the car. Start with the Mark sensor first, it cheaper.
Best of luck!

sutliffe

Sounds like the Camshaft Position/Reference Mark Sensor or the Camshaft Position Sensor. Start with the Mark sensor it's cheaper. Best of luck with the problem!

MB-Dude

Elle - Can you be more specific on the vacuum gauge operating intermittent? For example, when the gauge reads zero, is that when the engine performance is always the worst? If so, maybe you have a severe vacuum leak that is intermittent. Then it may be a matter of better understanding the specific driving conditions and engine parameters when the gauge reads zero. Just brainstorming thoughts.
Cheers,
Jeff