I ordered a KG Parts fuel kit and later upgraded the kit to include lines to the stock hard lines.

The first setup I received had a barbed fitting. No brainer - hook it to the stock rubber lines.

The second line I received had a crazy AN fitting with a plastic insert inside. It looked so cool I ordered another one and figured I could figure it out... Anyhoo I can't. HOW does this fitting work?




My first thought was it would "snap" into place but it doesn't.

Also - looking at the firewall from the front of the car are the hard lines (from left to right) Fuel Supply - Fuel Return - Charcoal Canister?

 

those are for fuel rails with snap fittings ... like mustangs etc...

 

^^^ Maybe but why are they supplied with my kit?

I have heard of these type connectors being supplied in lieu of the barbed fittings so they must hook to the stock hard lines somhow?

 

Those work well as long as 20 years from now you don't have to disconnect it. I personally like them as it's quick to disconnect/connect as long as the last "retard" didn't nip at it picks. Regardless though, plastic gets brittle over time no matter what. The last 07 STI I worked on had those if I remember correctly...

 

^^^ So how do these go on?

Seems there must be a piece that I don't have. Maybe a missing a ferrule or something?

I have two of the sleeves and two plastic inserts. Somehow they attach to the hardlines or what?

 

They slip right onto the hardlines and "clip on."