Workshop Manuals Factory service & repair Mini

Mini common faults and how to fix them

Faults that are well known on Mini models we hold manuals for: what the owner notices, what causes it, and the pages in our manuals that cover the repair.

Mini Cooper S timing chain: cold-start rattle on the N14 engine (2007–2009)

Symptoms

A rattle from the engine after a cold start, most often around 1,600–1,800 rpm. A rattle lasting only a moment at the very first start is described by Mini as normal, from the oil pump's first regulation cycle. A rattle that persists, or gets worse, points to the timing chain.

Cause

Mini service information SI M11 02 07 covers the R55 and R56 Cooper S with the N14 turbo engine built up to 4 May 2009. It gives the cause as insufficient tension of the timing chain, or a chain tensioner that has not been bled properly. Wikipedia records that a further service bulletin was issued in 2013 for failing timing chains and tensioners on the Prince engines (N12, N14, N16 and N18).

Fix

Work through the bulletin's checks to rule out other noises first. Then remove the chain tensioner, collect the oil from it, and refit and bleed it using special tool 11 9 340 as the Mini Cooper S timing chain bulletin describes. If the chain has stretched, replace the chain, guides and tensioner, following the Mini Cooper timing chain procedure.

Repair instructions on this site

Sources: Mini service information SI M11 02 07 (February 2011); Wikipedia — Prince engine.

Mini water pump: whistling or squealing from the front of the engine (R55, R56, R57, to 2009)

Symptoms

A whistle or squeal from the front of the engine at idle, at higher engine speeds, or both. It comes from the area of the water pump and the drive belt.

Cause

Mini service information SI M11 03 09 covers the R55 Clubman, R56 hatch and R57 convertible built up to June 2009. It gives two causes: the water pump itself, or the friction wheel of the drive belt tensioner. An improved friction wheel was introduced.

Fix

Find out which part is making the noise before replacing anything, as the Mini water pump bulletin describes. If the noise is still there at 1,000 rpm or higher, the bulletin replaces the belt tensioner's friction wheel with the improved part, number 11 28 7 571 833. If the water pump is the source, replace the pump. Check for coolant leaks around the pump at the same time.

Repair instructions on this site

Sources: Mini service information SI M11 03 09 (December 2009).

Mini power steering pump: cooling fan relay wiring on the R50 and R53 (to 2005)

Symptoms

The cooling fan for the power steering pump doesn't run when it should. Often there is nothing to notice at first, but without the fan the electric pump is left to run hot, and a failed pump means heavy steering.

Cause

The first-generation Mini Cooper (R50) and Cooper S (R53) use an electro-hydraulic power steering pump with its own cooling fan. Mini service information SI M32 03 04, a service action for cars with Park Distance Control (option 508), found that an improperly fitted electrical connection could stop the power steering pump's cooling fan from working.

Fix

Check whether the service action has been done. The Mini power steering pump fan relay sits above the fuse box in the driver's footwell; the bulletin moves the green and violet wire to the correct pin in the relay base using special tool 61 1 136. Then confirm the fan runs. If the pump has already failed, check the fan and its wiring before fitting a new pump.

Repair instructions on this site

Sources: Mini service information SI M32 03 04 (January 2005).

Repair instructions for every Mini model: Mini workshop manuals