170 /6 idle problem

The /6 in my 66 Valiant was running fine until a couple days ago when my fuel pump started squirting gas out of the side. So, I replaced the fuel pump and it ran good for maybe a couple minutes, but then started idling like crap and the only way to keep it running was to keep my foot on the gas or turn the idle screw all the way in, which barely got it iding fast enough to not stall. I adjusted the spring in the choke thermostat, which was really loose, but it didn't have any effect. Does anyone have any idea what the problem is? Thanks for any suggestions.