Hey peoples

I bought a old Taxi FG. It has dual fuel and it's not too bad. I am confused though with the difference with VPi and LPi. So i have a couple of questions and i would appreciate if the forum can help me out.

1) The FG is originally petrol and the gas plate is written 2012. So obviously its a custom install. But intake isn't a mixer... it has a injector that pumps directly into each intake port. The point of injection is about 2 inches before the petrol injector. So what kind of system is this? VPi or a LPi?
I will try and include a pic.

2) As the engine (and i would assume original) has 500,000km. What oil do you recommend? When she starts in the morning, it's not very happy. (it starts on petrol and automatically switches to LPG after 5min) Maybe it's misfiring, but it splutters a bit, it could be plugs.
But what oil and grade?

3) I did some coolant research and it seems that Nulon Long Life Green is the go. But what if i just used the Concentrate Coolant without any water mixed into it? So 10.5 litres of Nulon Concentrate into the cooling system after a flush
I've done this to my previous car and it worked a treat, but just wondering if anyone has heard or had any bad experiences doing this.

4) Since on the topic of cooling, how often is the water pump to be changed? Any decent brands?

5) any ideas where i can get the factory service manual?


any help on these questions would help me rest at night...