Hi just tried to change my spark plugs and they are very tight will not budge any advice welcome 

Good morning.What tool are you using?For me it's all about fitting a suitable socket,extension,a long lever and gently does it,rather than anything that you twist with your wrist.

Let the engine  go stone cold first if you haven't already 

Hi 

I am using a 16mm blue point(snap on) plug spanner and a 3/8" ratchet but I must admit the engine was hot

 

Yeah,as said wait for a cold engine and you'll be surprised what a long lever can achieve,gently.

Thanks but they should not be that tight but I'll give it a go 

All sorted just needed a bit of brute force and ignorance 

Many cars I have bought over the years have had plugs, wheel nuts etc., tightened far in excess of specification/requirements. I invested in a set of torque wrenches to ensure once the items have been successfully undone, they are torqued back to the recommended settings. Once you know how much effort is required to torque a wheel nut to the correct 100 lb/ft/135 Nm, you can see how easy it is to excessively tighten a spark plug.

Can me cynical, but each time one of our cars come back from a garage service, the first thing I do is make sure the wheel nuts are correctly torqued, and tyre pressures and fluid levels are correctly set.

Spark Plugs - Basic Knowledge, Recommended Torque and Tightening Angle for DENSO plugs.

http://www.globaldenso.com/en/products/aftermarket/plug/basic_knowledge/installation/index.html

Best investment in a toolbox is a LOONG breaker bar.  I bought my 36" one to undo a clutch hub nut on a motor bike years ago, but it's amazing how many times it gets pulled out.  If something's "tight" I no longer get the veins and eyes bulging, but go to the breaker bar straight away.  Everything is soooo much more under control, and you can hold the socket on the bolt, and a gentle tug 36" away will undo it...

Call me cynical as well but I treat the local tyre centre as I would the dentist as the sight of the air impact wrench gives me shivers of dread