Hi, my VU ute is dual fuel and runs well on petrol however when I switch it over to LPG and give it some gas I here a clicking noise (like a solenoid closing) and it nearly stalls. The revs go up and down when the accelerator is to the floor! I thought it could be the spark plugs but i got some new ones designed for LPG. Has anyone else had this problem and can help me on this?