Mechanics

SMOKE UNDER THE BONNET WHEN DRIVING HARD

1998 BMW 520 • 135,000 miles

1998 BMW E39, smoke under the bonnet when going up hill or driving hard. Replaced rocker cover gasket already. It looks like there is a leak, but cant find it. Smoke is on increase day by day that means leak is getting bigger. But there is no smoke on normal running or downhill, so far. There is also oil burning smell.
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Yadsingh4615
August 16, 2012.



Check the exhaust system for presence of engine oil. If any oil drops onto the exhaust system, smoking would occur. If there are any leaks, you need to locate the source and rectify it.

KHLow2008
Aug 16, 2012.
Try to find the source of leak, There is lot of oil deposit around CVV, Oil return hose and dipstick. What are the most common failure among these? Can the leaks on this side of the engine produce smoke under the bonnet?

Regards

Tiny
Yadsingh4615
Aug 16, 2012.
Yes if they can get to the exhaust.

You would need to clean up and recheck the source of leaks. Anything that has a connection are possible leaking areas.

KHLow2008
Aug 17, 2012.