Reliability
A known defect on the pre-facelift models was rainwater leaking into the rear of the car via the tail lights, resulting in puddles of water sitting under the rear seats which ultimately could rust out the vehicle around the rear suspension mounting points, as well as rotting the rear seat itself. Modification kits to resolve this were available for a time; some owners resorted to the use of liberal applications of silicone sealant. On pre-facelift models the boot hinge bolted directly to the glass. On these models, the wiring for the rear window wiper relied on the boot gas struts to have electrical connections to complete the circuit: struts with the necessary connections are now difficult to get hold of, leading to many earlier 309s having non-functioning rear windscreen wipers (and the wiring connecting to the struts also breaks). With the facelifted model the rear window was reinforced with steel around the edges and at the same time the heating element changed to a more traditional design. Better designed seals ensured no leakages made their way into the bootwell.
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