Basically I'm an idiot and have killed my car. I went through a flooded roundabout the other day to get to the shops. Went through and all was fine so off I go shopping. On the way back I went through the same flooded roundabout and when the car got out of the water it died within a few yards and I was unable to restart it (wouldn't even turn over). My dad gave me a tow and eventually I got it to fire and it now runs and starts. However I'm getting lots o smoke out of the back and have been for a few days. It stinks of diesel so I think it's overfilling. Drives really lumpy until about 3k then the boost kicks in like a tonne o bricks. (doesn't seem to smoke when in boost). I thought id hydrolic'd the engine but once it's in boost it runs smooth as always. Ive toyed a new egr valve and it just made the car feel quicker buys didn't go the smoke or the lumpy driving. I think it's boost related but I'm not sure. Any advice greatly appreciated.