BMW N55 engine

This page is a draft. It has not been approved yet, so read it with care.

Watch out for

Reputation: what owners and the press report. Tap one to see what to check.

Electric water pump failure Every version One source so far

What to check: Watch the temperature and listen for the fan running flat out.

BMW Tuning says failures are cited as early as 30,000 to 40,000 miles, while others pass 120,000.

Sources ¹
Leaking oil filter housing gasket Every version One source so far

What to check: Look for oil on the belt tensioner and drive belt.

BMW Tuning says the oil commonly reaches the belt, which can slip or snap, and recommends replacing the housing on engines past 100,000 miles.

Sources ¹
Leaking valve cover and PCV valve Every version One source so far

What to check: Look for oil on the plug threads and smell for burning oil.

BMW Tuning says the valve cover typically lasts about 100,000 miles, and that its built-in PCV valve eventually fails.

Sources ¹