  A model incorporating simultaneous superconducting and lattice instabilities
has been studied in detail to estimate the nature of coupling and inter-play
between them. The phase diagram is obtained in the temperature-filling plane at
different values of the parameters of the model. It is found that a pseudogap
develops in the distorted phase that inhibits the appearance of the
superconducting transition. The superconducting instability is strongest for
the regime of filling where the van Hove singularity in the 2D density of
states is close to the chemical potential. The pseudogap, developed in the
distorted phase, is a function of temperature via the temperature dependence of
the distortion itself. Transport properties, namely resistivity and thermopower
are found to be strongly dependent on the variations of the pseudogap.
