I have a '98 Peugeot 406 with a 2.1TD engine, which seems to work fine, but there is a slight niggle with it. When I first start the car in the morning, a few seconds after it starts I can hear and feel the engine kind of stalling but it never does. The idling speed drops from the about 800 to 750 and then back up to 800 - all within a second. After that it idles perfectly. Am I right to assume it does some sort of idle speed adjustment or something? Now the other problem I have, which may or may not be related to the one above, is when I drive the car at high speeds... say over 90mph... I can again feel this.. shuddering, like someone has lifted the foot off the accelerator for a second. Or an even better description - a side wind! I never paid much attention to it until recently I was cruising on the motorway at just over 90mph and again felt this shudder, and when I eased of the accelerator, there was a "clunk" from the car somewhere and engine simply stalled with the orange diagnostics light on... I pulled over to hard shoulder, switched the ignition off and then back on - it started without a hitch and I got home without any further troubles. But I can still feel this when starting the car from cold (although it doesn't always happen). I bought the car at 74k on the clock and has now done 86k. It had this problem from the beginning. Its glow plugs have been replaced at around 66k along with the timing belt and water pump. Last service was at 81k with an oil change, oil filter change and air filter change. It's due for another service soon. I am not a petrol head (or a diesel head for that matter!) but could the above problem be related to too much air or fuel being fed into the engine causing it to "splutter"? Or could it be something else? The car otherwise runs fine and starts first time every time. Any input appreciated ! :) Thanks Alex