406 Coupe Brakes and Idling

I have two problems with my 406 Coupe (yr 2000) that I have been unable to
solve:
(i) idling problems
Particularly in cold weather, the idle speed seems to drop from 800 to
around 700 and the car sounds quite 'rattly'. I've had the car from new
and this has always been there. Peugeot dealers couldn't fix it. I've
recently found out that there is a faulty pinking sensor registered on the
ECu read out. Could this be the cause? How easy are these to change and are
they expensive?
(ii) Brake vibration
On braking at higher speed the car vibrates quite badly. A Peugeot dealer
seemed to cure this by basically grinding down the front disks to even
them out. But, its back again. What could this be, and how would I cure
it?

Any help with this would be great.

Flashster

 

| I have two problems with my 406 Coupe (yr 2000) that I have been unable to
| solve:

| (ii) Brake vibration
| On braking at higher speed the car vibrates quite badly. A Peugeot dealer
| seemed to cure this by basically grinding down the front disks to even
| them out. But, its back again. What could this be, and how would I cure
| it?

If you drive the car particularly hard (ie. repeatedly jam the brakes on at
high speeds) the heat when the pad touches the disc can cause some of the
brake pad material to transfer to the disc and form a cementite. The outcome
of this is that braking is uneven, particularly at high speeds where it
feels bumpy. Eventually this becomes bad enough that the discs need to be
ground down. This is what many mechanics have told me and seemed to hold
true recently as a friend of mine burned the brakes out on his Honda S2000
after braking from (no doubt extremely) high speed!

Do a google on "disc cementite deposit" for more info.

Hope this helps.

Dom

 

Idling problem could be due to faulty ignition coils, might be since you
had this since new, they have been replaced to a new model. This was
the case of my 2001 at least. (there are 6 of them, so be aware of the
bill ...)

I have noticed that the original disks are very sensitive to rusting, at
least since I mosty use my Coupe out of the garage to wash it and back
in againt I think theese brakes are worse than others I have expirienced.

/Hazze

 

Thanks guys. As I don't drive my coupe very hard at all, I guess it may be
the rusting causing some pitting in the disk??

 

ii - Braking

Dont know if this is of any use, but did see somewhere that if you have an
auto (dont know if you do) then holding the brakes on whilst at (say) a
roundabout with the car in Drive will warp the discs, even after moderate
braking. Apparently they are known for it.

Warped the discs in my 406 by braking from high speed, then holding on
roundabout at end of m/way slip off ;-)

HTH

M@