I have done my B.Tech IN ECE and now I want to pursue my MBA but I haven't taken any entrance exams, so is there any chance to pursue MBA in any of the colleges which can give 100% placement assurance.

You need to get into reputed B School for your degree to be valued by the corporate world. You should look at giving your CAT exam in November 2011. Apart from CAT, there are other reputed B Schools which have their own entrance tests. These are , FMS - DELHI , XAT , N MAT - NARSEE MONJEE , SNAP