This occurred to one of our Peugeot 1007's in February 2012. It had travelled just over 20,000 miles in 5½ years however the problem could equally apply to our other 1007's; the Peugeot 206 and the Citroen C2 & C3 which share the same chassis.
Spring breakages is not peculiar to Peugeot - it is the ever-lasting cost-cutting and weight-reducing that the industry is subject to. Modern springs are little more than a wire.
We never heard of a coil spring breaking in 1950's cars - but they were mighty heavy and about twice the wire diameter. By comparison, modern springs are light and despite modern materials, may be more brittle to get the performance required.
A dealer emailed another owner: "We have indeed seen many spring failures on 1007 and some result in tyre damage. So whilst we agree with your point, unfortunately we are not the best recipient of your email to do anything about it. You’re best corresponding with Peugeot customer service."
Spring breakage occurs on many modern cars however this incident caused the ends of the spring to rub and burst the front tyre which deflated immediately.
With some difficulty the spare was fitted but the wheel could not turn as the spring was pressing outwards against the tyre.
It is not just the failure that concerns, but the safety implications of a front tyre being burst by the coils of the broken spring whilst moving
Failure of the main spring allowed the lower coils of the spring to extend beyond the spring seat and jam between the seating and the sidewall of the tyre.
It appears that the damage occurred because of the shape of the spring. If it breaks anywhere on the larger diameter then the ends are not constrained by the spring seat and the loose end can be forced down between the spring seat and the tyre with some force.
If you are unlucky, one of the sharp broken ends can be forced into the tyre sidewall resulting in almost instant deflation.
OR - the coil can be forced down between the tyre and the mounting with resulting high friction, smoke and almost instant deflation.
This is how the lower part of the spring should sit in the spring mounting.
There appears to be a weak point caused by flexing and/or corrosion just as the spring comes away from the mount and many springs seem to fail at this point. As can be seen from the picture; if the lower coil of the spring breaks then the upper coils can be forced over the spring mount on the damper and almost instantly puncture or wear away the sidewall.
This is the assembly drawing of the Peugeot front suspension; the force also broke the top rubber mounting.
and here, the remarkably similar drawing for the Citroen - note the spring catcher (bottom left, item 12).
this is the standard set-up as supplied by the factory.
The upper coils have a greater diameter than the spring seat on the strut so should the spring break, the upper coils will be forced down past the spring seat.
subsequently (27th February) broken parts sent to Peugeot for investigation at the request of VOSA
the final report received on 10th May states "the official response from the manufacturer concludes there is insufficient evidence of a wider problem to warrant an action within the terms of the Code and of course there were warnings of the concern prior to the tyre failing"