sucking/rattle noise

had my car serviced the other day by accquaintance… had the whole lot done plugs filters cam belt etc..
when i got the car back i took it out and heard rubbing noise, so took it back and mechanic recond cam belt was too tight,changed tenson on cam belt, which has stopped that noise.. drove ot for about an hour combination of 'a' roads, motorway all good, then took it out today and found that i have a new noise! the tick over has allways been set low and for the last year had not had any probs with that, but now when it idels it revs up then back down, got so low alternator light flashed and it nearly stalled, and when i put my foot down it makes a rattly sucking noise through exelleration like its struggling? also noticed that getting more vibration through the accelerator than usual?                                         anybody any ideas why this has happend? its going back to garage tommorow so hope it will be sorted as need it for the weekend, it was noise free before service! :dontknow:

mines the same did u find out what it is??

I would check for an air leak somewhere, sounds like a pipe might be split or not connected back up properly.

Rev the engine slightly from under the bonnet and listen out for air escaping.

T

cheers will do