Car Model Guide/ Issues/ Panoramic roof drain blockage and water ingress

Panoramic roof drain blockage and water ingress

Attaches to E91 at chassis level · Body & corrosion · carried by 17 variants across 1 chassis

Overview

Panoramic roof drain blockage and water ingress is a common fault recorded against E91 at chassis level, at any age. It shows up as damp headlining, water in the footwells, musty smell, and then electrical faults as modules get wet. Where it's documented, the repair runs €150–€1,200 (drain clearing at the low end; a drowned module and soaked carpet at the high end, costs dated 2026-07), and it can be checked before you buy. 17 variants across 1 chassis in this database inherit it.

€150 – €1,200

drain clearing at the low end; a drowned module and soaked carpet at the high end · costs dated 2026-07

Likelihoodcommon

Typical onsetany age

Detectableyes

Walk awayno

Evidencedocumented

What happens

Symptom. Damp headlining, water in the footwells, musty smell, and then electrical faults as modules get wet.

Cause. The panoramic roof's drain channels block with debris and the water finds its way into the cabin instead.

How to check it

Static checks

Lift the boot floor and the front carpet edges and feel for damp. Check the spare wheel well for standing water. A wet footwell on this chassis eventually means a failed module.

Engine off, ideally on a lift.

Body & corrosioncommonDetectable at viewingevidence: documented

Every variant that carries this

Variant	Chassis	Body	Years	Risk	Good buy	Cost as % of good buy
318i N46	E91	wagon	2005–2011	R3	€3,300	20%
320i N46	E91	wagon	2005–2007	R3	€3,600	19%
320i N43	E91	wagon	2007–2011	R4	€4,200	16%
323i N52	E91	wagon	2005–2007	R2	€4,300	16%
325i N52	E91	wagon	2005–2007	R2	€5,050	13%
325i N53	E91	wagon	2007–2012	R4	€5,550	12%
328i N52	E91	wagon	2006–2012	R2	€5,450	12%
330i N52	E91	wagon	2005–2007	R2	€5,950	11%
330i N53	E91	wagon	2007–2011	R4	€6,350	11%
316d N47	E91	wagon	2009–2011	R5	€4,450	15%
318d N47	E91	wagon	2007–2011	R5	€4,350	16%
320d M47	E91	wagon	2005–2007	R3	€4,050	17%
320d N47	E91	wagon	2007–2012	R5	€4,650	15%
325d M57	E91	wagon	2006–2010	R2	€5,500	12%
325d N57	E91	wagon	2010–2012	R3	€7,650	9%
330d M57	E91	wagon	2005–2008	R2	€6,300	11%
330d N57	E91	wagon	2008–2012	R3	€9,050	7%

The last column is the point. The same repair is an inconvenience on one variant and a reason to scrap the car on another. A failure costing a quarter of the vehicle's value changes the purchase decision regardless of how rare it is.