peugeot 307 fault anti pollution?

A few months after picking up our used peugeot 307 (Diesel) whilst driving, the car started to register an "Anti pollution fault" on the interior screen, with a loss of power for a few seconds, then the power would come back on, without the need to stop.

Once the anti pollution message had gone from the screen, one of a few things would happen.

Passenger airbag would disable and light up on the dashboard
Engine management light on the dashboard would come on
All readings on the dashboard would go off and all the lights on the dashboard would start flashing, the speedo, fuel gauge, rev counter, would all go to zero, for about 20 seconds, then all would come back on and the passenger airbag would light up permanently
Once any one of these things happened, all the rear lights would start to play up. Brake lights would stay on permanently, then they would flicker, etc.
The boot door stopped locking, when ever all the doors were closed, the boot door would click and open again without the need for the handle to be used. Locking all doors then closing the boot would finally get it to close and lock.
On rare occasions, the accelerator pedal would lose all power with the engine on tick-over only.
Turning the engine off whilst parked for a few minutes then restarting the engine always rectified the faults, until the "anti pollution fault" message came on again.
It could be 50 miles down the road, it could be 2 miles, completely random.

You really couldn't make it up, I read peugeot websites/forums, googled questions about the peugeot 307, etc, all with no solution to the problem. We even paid auto electricians investigate.
As the anti pollution fault seemed to be the start of the problems, so my first plan of attack was good old redex. For about 3 tanks of diesel once added to fuel tank, this seemed to make things a little better, still the problem persisted.
Next, I changed all the bulbs in the rear lights, no joy there.
Next plan of attack was to have the fuel lines blown out. I was told that there are two fuel pumps on the peugeot 307s, one that works on low gears then switches to the other fuel pump for higher gears. I still don't know if this is true, but it was suggested that sometimes the higher gear fuel pump leaves tiny iron filings in the fuel lines.

Anti pollution fault was causing so much grief that we even started looking around to buy a different car. Once in a supermarket car park, I locked the car up and it turned the stereo of the peugeot next to us off.
The gent asked us to open and close the car again and sure enough it turned his factory fit radio off!

The fault was solved by a complete fluke.
On a drive up north, as I came off the good old A1, I heard a rattling noise. I pulled over to see the silencer/back box of the suspension hanging down tapping against the floor.
The RAC took off the back box, it had snapped just before it, on the mid pipe. I drove the car another 130 miles back without a problem, as the car goes into "Economy mode" actaully saving diesel on what it was using with the full suspension attached!
The peugeot 307 doesn't have clamps holding the exhaust system up, it is attached to the car via two rubber mounts. Welded rods on the back box push into these mounts. The side facing mount/bung had broken.

This revealed that where the pipe had come away had been corroded and with the corrosion facing the underside of the car, it was impossible to spot.
£40 outlay for a new mid pipe section and a new rubber bung later, we now considered with some urgency, selling the car and buying one "that works"

I drove out from the exhaust centre with a long trip to Liverpool due that afternoon.
The anti pollution fault? Gone!
The fault with the lights and the boot not closing etc, gone!
The engine management lights, the dashboard knocking off, the airbags deactivating, all appear to have gone! *Touch wood*

So if you have the "anti pollution fault" and various electrical faults on your peugeot 307, before you do anything else, get a garage to remove your exhaust from it's rubber bungs and check the underside, car facing part of your exhaust!

Chances are your exhaust is corroded somewhere and it is sucking in air causing the fault!

Simon
September 2012