Rough running and no idle M103 engine Possible cause

1986-1995 : 200TD, 200CE, E200, 260E, 300E 2.6, 300E 2.8, 300E, E320, 400E, E420, 500E, E500, 300CE, E320, 230TE, 300TE, 300D 2.5 TURBO, E300 DIESEL, 300TD, 300E 4MATIC, 300TE 4MATIC, E36 AMG
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Model you own: w124
Location: Melbourne

Rough running and no idle M103 engine Possible cause

Post by benzy53 » Tue 12 Feb, 2019 5:12 pm

The other day I fixed an oil leak on my friends car ( top timing cover seal ). During that process you have to lift the
rocker cover and remove/loosen that little rubber hose going from the rocker cover to the intake manifold next
to the air filter housing. His rubber was rock solid and not flexible at all. During that process a bit broke off. After
the job was done and we put everything together except for the rubber hose that was broken. The car ran horrible
and no idle was possible. As soon as we took the foot off the accelerator the engine stalled. After I blocked both
holes with my thumb the car ran as it should. If you have a leak in that hose it has a massive impact on the performance
of the engine. Having idling or running issues one of the main reason is a vacuum leak. I believe if you are faced
with these issues pay GOOD !!! attention to that hose. A new hose has been ordered.

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Model you own: w124
Location: Melbourne, Australia

Re: Rough running and no idle M103 engine Possible cause

Post by dhaigh » Thu 14 Feb, 2019 3:01 pm

Well done Benzy53..!!
This should be a maintenance item. Cheap part available on Gumtree or eBay for approx. $20. Part nbr 103 094 0082
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