Hey guys been lurking here for a while finally going to post something and of course it's a problem. I just recently installed a new fuel pump(yesterday) and it drove fine for a quick trip around the block but now it's rough to start and idles very rough. It hesitates when I give it gas any ideas what could be causing this?

 

http://www.christurnbull.com/project...-g35-fx35-etc/

Assuming the pump is larger than the stock one, you probably didn't drill out the regulator orifice and the swirl jet.

Edit: You probably have to alter your fuel tables in whatever software you are tuning with. Likely running rich since the pump is designed to flow more fuel

 

Its actually an oe fuel pump on a mainly stock car which is why this is especially puzzling

 

have you tried cleaning the filter and injectors?

Also, if you want another pump to test, I have my oem one sitting around if you want it. PM me if interested