rough idle at stop - 1987 300 E @ 190 000
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M B 300E 1987
rough idle at stop - 1987 300 E @ 190 000
Without warning, after short trip/then short stop/ on restart, engine missed badly (like not on all cylinders). MB service repaired, as below, then same condition resumed after 3 weeks.
MB initial repair included replacement of one fuel injector and cleaning all others + new seals. On following repair, MB insisted on replacement of fuel distributor (remanufactured Bosch $600 unit from Performance Products - couldn't get one to work so reordered another), then noted that fuel and oil were washing into cylinder #5, then replaced all valve seals, replaced all spark plugs and tested compression - O K.
After this second 3 weeks in the shop, car runs O K - maybe better than before, but has off and on rough idle. MB service only idea is to go back in and install all new injectors or install $2,000 + MB fuel distributor unit. They have refused to contact MB technical.
Vibrations/rough idle occur at stop, say at traffic light while in gear, in Drive, stumbles, then recovers. Recent emission test showed "high level of hydrocarbons" at idle, but passed overall. I have used Techron, now on second tank dose, and tried a little highway speed driving and notice some improvement. I don't believe it is a motor mount issue; vacuum gauge indicator is normal. However, problem remains.
Any diagnostic ideas would be most welcome. Thanks.
MB initial repair included replacement of one fuel injector and cleaning all others + new seals. On following repair, MB insisted on replacement of fuel distributor (remanufactured Bosch $600 unit from Performance Products - couldn't get one to work so reordered another), then noted that fuel and oil were washing into cylinder #5, then replaced all valve seals, replaced all spark plugs and tested compression - O K.
After this second 3 weeks in the shop, car runs O K - maybe better than before, but has off and on rough idle. MB service only idea is to go back in and install all new injectors or install $2,000 + MB fuel distributor unit. They have refused to contact MB technical.
Vibrations/rough idle occur at stop, say at traffic light while in gear, in Drive, stumbles, then recovers. Recent emission test showed "high level of hydrocarbons" at idle, but passed overall. I have used Techron, now on second tank dose, and tried a little highway speed driving and notice some improvement. I don't believe it is a motor mount issue; vacuum gauge indicator is normal. However, problem remains.
Any diagnostic ideas would be most welcome. Thanks.
