diff --git a/integrators/tps2.py b/integrators/tps2.py
index 729281b055d999cd5da4cb4c0d769d5bfcb265ed..ad55678cd315074a4cb5e422a251fa7678ae760f 100644
--- a/integrators/tps2.py
+++ b/integrators/tps2.py
@@ -235,7 +235,7 @@ class TPS2(_tpsx.TPSX, \
       RHS = self._Q.dot( f )
     
       w, succ = scipy.sparse.linalg.gmres(self._LHS, RHS , x0=None \
-        , tol=self._solvetol, maxiter=4000, M=None)
+        , tol=self._solvetol, maxiter=4000, M=self._preconditioner)
       self._Mag.v.gf.vec.FV().NumPy()[:] = self._Q.transpose().dot(w)
     
       diff_gf.vec.FV().NumPy()[:] = self._Mag.v.gf.vec.FV().NumPy()-oldIterate