noise from underneath the car

[deanster12]

everytime i start my car it starts fine but theres an irritating rattling coming from the underneath of the engine it gets worse when i put my rear window demister on or my heaters full blast the car gets all juddery.could this be my exhaust on its way out or something loose.

[deanster12]

any ideas anyone on what this could be as ive just had a new head gasket, a skimmed head and had new valves and camcrank ,a new ignition coil ,new sparks battery a new starter motor .new tyres ,new driveshafts im realising citroen saxos are not for me and this one should drive like new but im still having problems.