The car is a 2002 C270 cdi. First time car would not start. Could not start three days running. Called AA. Squirt 'easystart' with foot on throttle and it started on first day. AA suggest change glow plugs. Went to garage. Could not find anything wrong. Took car back.

Next day could not start again. Called AA. Squirt 'easystart', foot on throttle and it started. Went back to garage and conveyed AA suggestion re changing glow plugs. Garage checked and changed glow plugs and changed filter. Took car back.

Third day, again could not start. Called AA. Squirt 'easystart', foot on throttle and it started. AA reported a 'lazy pump'. The car is now in the garage (not Mercedes dealer).

Has anyone experienced this problem and know how what the problem is?

Thank you.