how many months are you allowed to apply for citizenship after passing the life in uk  test.or is there any time limits. i was granted an indefinite leave to remain in the uk last march 2005...i was out of the country last march2006 for 7weeks...would it affect my application?

Provided you meet all the other requirements then you can apply as soon as you have passed the LiUK test.

Requirements:  Please see this page of this web site that the host ( E Fidan
Administrator) has kindly set out. http://www.lifeintheuktest.me.uk/index.php?title=Application_Stages  

As far as I am aware the test certificate is valid indefinitely