Despite the shallow convective envelopes of \delta Scuti pulsators , solar-like oscillations are theoretically predicted to be excited in those stars as well . To search for such stochastic oscillations we organised a spectroscopic multi-site campaign for the bright , metal-rich \delta Sct star \rho Puppis . We obtained a total of 2763 high-resolution spectra using four telescopes . We discuss the reduction and analysis with the iodine cell technique , developed for searching for low-amplitude radial velocity variations , in the presence of high-amplitude variability . Furthermore , we have determined the angular diameter of \rho Puppis to be 1.68 \pm 0.03 mas , translating into a radius of 3.52 \pm 0.07 R _ { \odot } . Using this value , the frequency of maximum power of possible solar-like oscillations , is expected at \sim 43 \pm 2 cd ^ { -1 } ( 498 \pm 23 ~ { } \mu Hz ) . The dominant \delta Scuti-type pulsation mode of \rho Puppis is known to be the radial fundamental mode which allows us to determine the mean density of the star , and therefore an expected large frequency separation of 2.73 cd ^ { -1 } ( 31.6 \mu Hz ) . We conclude that 1 ) the radial velocity amplitudes of the \delta Scuti pulsations are different for different spectral lines ; 2 ) we can exclude solar-like oscillations to be present in \rho Puppis with an amplitude per radial mode larger than 0.5 ms ^ { -1 } .