I'm going crazy!! I recently moved home and so have a different oven. It's gas and Iv had a few problems with its temperature so I have a thermometer inside it to make sure it's getting hot enough etc. Anyway my vanilla cake especially is not turning out right. It sinks in the middle, burns at the bottom, has LOADS of holes and even one huge hole meaning there's no middle to the cake. Plus the texture is not great to eat!!.. I don't know what's going on, Iv never had problems before so I'm so frustrated. At first I thought maybe my mixer was Over mixing so I started from scratch by hand and it's turned out exactly the same with a huge hole in the middle and tastes kind of chewy with a burnt bottom!!! I'm baking at 180c and the recipe I used was..

220g butter

220g caster sugar

220g self raining flour

4 eggs

2 tsp vanilla

2 tsp baking powder

someone please help.. Is it my fault or do I need a new oven?!

Did you have a gas oven before?

No I had an electric oven.

have you tested the temperature of the oven with an oven thermometer? You might want to get one and move it around in the oven to see if there are hot spots in it. Mine is hotter at the back left than it is in other spots, so things I put back there bake faster.

With gas ovens what plays is the positioning of cakes. Heat rises, so the higher you place the cake, the hotter it will be and the quicker it will cook. To slow it down, bake at a lower position. Of course this is thinking about ovens we have in the UK where the fire is at the bottom in the back. It might be different in other parts of the world, so why don't you experiment with cupcakes - bake a couple low, then bake a couple high and see the results.  The hole in the middle must be you opening the oven before 3/4 of the time had passed. Hope you can find the right way to use your oven.

The hole in the middle could be caused by you pouring the batter into the pan too fast/hard creating a bubble.  I had that happen a few times until I figured it out :)  

You say you are using a thermometer but -- what kind?  Yes, ther are many different ones.  Those little round rounds with a finger-like pointer that are available at most grocery stores usually are very! unreliable :(   The best type to get is a murcery -- oh my! I've forgetten who makes it.  Best place to get one is an appliance parts house.  Some 15 yrs ago they cost about $20 (US $)   Hope that helps.