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[terry paget]

The next thing I would check is that the calipers slide freely, and that the pistons move.

On my X reg estate pedal travel is noticeably longer than on my similar mileage V reg estate. I put this down to master cylinder wear, but soon readjust to it.

I know this is going off on a slight tangent, but I had the same with my Omega, with the brake pedal having a long travel but still working. Weirdly, after changing the abs block, the pedal is firmer and still as sharp, if not sharper than before.

`Changing the ABS block involves bleeding the system afterwards, so if there was air in the system before the bleed will have improved things.

[TheBoy]

The next thing I would check is that the calipers slide freely, and that the pistons move.

On my X reg estate pedal travel is noticeably longer than on my similar mileage V reg estate. I put this down to master cylinder wear, but soon readjust to it.

I know this is going off on a slight tangent, but I had the same with my Omega, with the brake pedal having a long travel but still working. Weirdly, after changing the abs block, the pedal is firmer and still as sharp, if not sharper than before.

That does smack of a bit of air in ABS valve unit. Tech2 has a function to help remove the air

[iansoutham]

Mine is all good, no air, etc....

What I was trying to say is that he could have old fluid or some other problem with the brakes other than the materials that would not be easy to diagnose.

I would fix the vacuum problem (if present) and then maybe get someone to do a thorough bleed as TheBoy says to make sure there is nothing else.

[johnnydog]

During an MOT test, it is likely that the mot tester applied much more pedal pressure during the brake test than is normally used during daily driving. If the sliders in the calipers carriers are partly seized (due to perished rubbers causing dirt / water ingress) applying that extra force can move the carrier to a position where the rusty part of the sliders results in the carrier seizing on. This can cause a more wooden / dead / solid feeling in the pedal as the carrier isn't 'releasing' the pad after a brake application.
The same principle also apply to the caliper pistons if they are corroded on the exposed area - they can seize causing the same symptoms following a heavy application - one of the reasons why you shouldn't let your brake pads get too low before changing them. Low pads result in a bigger area of the pistons being exposed which can result in corrosion on the exposed part, which only becomes a problem when the piston is pushed back when new pads are fitted and causes damage to the inner seal.
Worth checking the above, I would suggest.

[terry paget]

During an MOT test, it is likely that the mot tester applied much more pedal pressure during the brake test than is normally used during daily driving. If the sliders in the calipers carriers are partly seized (due to perished rubbers causing dirt / water ingress) applying that extra force can move the carrier to a position where the rusty part of the sliders results in the carrier seizing on. This can cause a more wooden / dead / solid feeling in the pedal as the carrier isn't 'releasing' the pad after a brake application.
The same principle also apply to the caliper pistons if they are corroded on the exposed area - they can seize causing the same symptoms following a heavy application - one of the reasons why you shouldn't let your brake pads get too low before changing them. Low pads result in a bigger area of the pistons being exposed which can result in corrosion on the exposed part, which only becomes a problem when the piston is pushed back when new pads are fitted and causes damage to the inner seal.
Worth checking the above, I would suggest.

Thanks for the thoughts. I suppose both sides might have corroded similarly, but in my experience of running 6 Omegas for 10 years I have known rusty pistons and sticky caliper slides - I stock spare calipers and change them when they stick - one side fails first and the brakes pull to the other side. This car pulls up straight.

Thanks to this forum an engine misfire was rectified over Christmas, and daughter and boy friend departed in it on Tuesday for a walking holiday in Dartmoor - good luck to them. I expect to see it again at Easter. It is a fine car, powerful, large, quiet, fast, top of the range (a CDX), everything works, even the aircon. They love it, so they should. It's just that I fret about the brake initial lack of grab, compared with other Omegas.

 Shucks, sister's Meriva is so sharp I find stopping gently difficult.

[terry paget]

The next thing I would check is that the calipers slide freely, and that the pistons move.

I suppose that's all that's left, and yet it seems unlikely that both sides would fail similarly, and if one side was sticky the brakes would pull to the other. Also, when I changed the pads last year I did look for these things.

There's plenty of other things it could be, but they're all much harder to examine or prove faulty so you work up to them in a methodical way.

Daughter and boy friend left in this car Tuesday for Cardiff, then Devon, no word since, so I presume car is OK. Looking ahead, you say there is more to check but more difficult. At Easter, if I am bored, I shall explore further. Obvious things to change are servo, master cylinder and ABS block, in that order. Do you agree?