My car is fitted with manual fuel pump and a CNG kit is installed. Additinally I have installed a new electrical fuel pump. The problem is that when I switch ON ignition the fuel pump also starts but it dosn't suck fuel from tank specially when engine is cold, but can pump fuel already present in its base. When engine starts it also starts sucking fuel from tank. Could this issue be solved by installing a relay with this pump ? As battery current is ok and it seems that fuel pump need more current to perfectly work.