Clicking could could be the lighting relay switch unit.get someone to operate it and put your ear to the fuse box on the right side ,next to the wing,not normally a loud unit,but??? Replacing may be the answer.
Hissing sound can only be air (or water escaping, and spraying onto hot metal) from somewhere.maybe your "mad spell" put a little more pressure/vacuum on some of the pipework and loosened ,or split it at the jubilee clip or fastener,and is underneath them,and will only be seen when you loosen them off and check for small splits./holes.
JUST HAD ANOTHER THOUGHT,HOW ARE YOUR BRAKES ??HAVE YOU LOST THE VACUUM SERVO
ASSISTANCE,I.E VERY HARD PEDAL AND BRAKING EFFORT.IF SO THEN THIS IS THE HISSING SOUND AS THE AIR BLEEDS OUT FROM THE SERVO UNIT,AND IS NOT BEING HELD IN THE RESERVOIR , YOU MAY HAVE DISLODGED THE AIR INLET PLUG FROM THE INLET MANIFOLD INTO THE UNIT.SO YOU HAVE NO VACUUM IN RESERVE.CHECK THIS URGENT.

 

i just checked the car for the hissing noise and its coming from the injection part cos when i unplugged this wire from the injection system it stopped? what cud it be?

 

What exactly did you disconnect?

 

Could just be the IACV indexing.

 

his first post on this said he had a whistling sound ??

 

Yep, high pitched whining noise. I don't think he's describing it right as hissing. Nothing can hiss with the engine off.

 

He posted on my user wall that the hissing ( only when he turns off the engine...or so he says in this particular thread.. )
has only been present since taking the engine up in revs to clean out the cat
( a local mechanic advised him to and he made a thread asking about it on here )

Might just be the radiator fan running on longer than usual after switching off ( since he never usually revs the engine or anything but eco-cruises for mpg )

or maybe a slightly leaky/loose expansion tank cap?
( maybe higher pressure in the coolant system due to warming the engine up more than usual? )

 

Video clip of the noise would help, my guess is the noise has always been there, but paranoia has set in. Also turning the ignition on and off at random will cause the injectors to click.

 

as ashy said, it's probably all in your head mate.

My injectors click occasionally, and if I have absolutely ranted her after a short spell of driving overly eco, my fan stays on for a little while longer than usual. It won't be anything major.

If it is you would have experienced power loss etc.

are there any other symptoms/weird things going on?

Dan