Context. Many transiting exoplanet surveys are now in operation, observing millions of stars and searching for the periodic signals that may indicate planets orbiting these objects. Aims. We have tested the performance of transit detection algorithms using real WASP data, avoiding the issue of generating the appropriate level of white and red noise in simulated lightcurves. We used a two-dimensional search method, the box-least-squares (BLS) algorithm, and two- and three-dimensional versions of the analysis of variance (AoV) method. Methods. After removing any potential transiting candidate or variable objects, transits were injected into each lightcurve. We performed Monte Carlo simulations, testing the recovery of injected signals i...