Mazda 929 Fuel Injection problems + Question
 

Hey there! I'm new to cars (I'm just 19) but I spend more time with my car, than with my friends. :D I got my Mazda 929 from a senior for 300 Litas (~85euros). It came with V6 3 Liter engine. It has about 140kW, and it's RWD! (Model: HC, 1987)

Recently, I had problems with fuel injection. The engine runs on petrol but I also have gas installed. The car runs perfectly on gas (except you can't turn her on with gas, because it can damage the engine) but when I switch to petrol the car starts shaking, RPMs drop, car makes a lot of smoke.

I recently changed my cylinder head covers, because they were leaking oil. After I got everything as it used to be I tried to start my car. The car won't start. It was giving life signals, was shaking and trying to start. I don't know what to do and where to start. I took photos before and during the repair and all pipes, other things are in the same place just like they used to be. What could be the problem? The vacuum?


Also could you help me identify this thing? I don't know what is this thing but it makes a strange sound when my car is in ignition. I found the part in Mazda Catalog but it's unnamed. Could you help me identify it? MAZDA

which part?
 

the link shows a lot of parts, which one is it?