Check the cold-start sensor, too. Mine had that ages ago and it was the sensor. Had to crank away and pump the accelerator like a loony to get it to start.
Where are the cold start sensor and the idle valve? Have spotted one of my brake pad springs has come off on that wheel so i expect that'll be the rattle....
Idle valve .Take the pipes off either side of the valve and spray through .No cold start sensor that I know of on the turbo .Water temp sensor for the ECU can make it hard to start if it gone tits up .