the last several jobs i did .. my dodge truck / the pinto / now the stang ... i used the highly recommended urethane hi build yellow primer .. i dont like it a bit better than the old standard red oxide .. doesnt cover sand scratches a bit better ..
I haven't had that problem... but I really "hose" it on, to the point of almost running... and usually it's 3-5 very heavy coats depending on what I need to block out.