Hi hope someone here may be able to advise. I have a 406 1.9TD. When the engine is initially started the brake servo does not function as it used to till the engine has run for a few minutes, it scared the hell out of me yesterday when I got to the end of my road approaching the main road and pressed the pedal to get that horrible solid feel and no real braking action. After running for a while it seems OK BUT if the brakes are used several times in succession the assistance appears to disipate. I've checked the valve in the servo vacuum pipe and that is OK ( only passes air in the correct direction ) put finger over end of vacuum pipe and there is suction there I don't have a vacuum gauge to measure the suction) I need to resolve this problem as I'm off to the mountains soon and would hate to run out of brakes on some of those hairpins!
It MAY be relevant but the engine was recently changed by a garage and since then the engine is prone to misfire when stone cold.
Thanks
Ron