Trouble seating injectors after pulling intake

B6/7 S4/RS4
#1

So I spent 12 hours today replacing the valley pan gasket. This was by far one of the most tedious car repairs I’ve ever carried out, mostly due to the immense amount of cleaning required, but also BC I broke one of the small vacuum hoses, and damaged an injector clip.

Got everything torqued down with a proper torque wrench, connected hose, etc, but the car runs like sh*t.

I had a really tough time re-seating the fuel rail and injectors. No matter how much I pressed down on the fuel rail the injectors didn’t seem to really seat in their bores.

Is there a technique to persuade them in? Thank you.

#2

a little grease on the o-rings helps. and if it’s running like shit, check out the vacuum lines on the front of the mainfold. maybe you pulled one off or broke a connector like I just discovered on my car

#3

From the sound of it this is a NA 4.2 S4. You shouldnt really have to worry too much when you tighten down the fuel rail it should help push the injectors in there bore. The injectors dont like to go back in but you really need to check and make sure that the little rubber O ring didnt come out or get lost that helps seal the port. Usually some lube on the rubber O ring and a making sure they are warm help them getting seated.

Is the rail flush with the mount on the intake…
Usually the runs like shit is a vac leak after taking everything apart. You can check vac leaks with starter fluid spray it around and see the spots where the RPMs go up when you spray or look in vag com at the instant fuel trims. That can help find the spot very quickly as well.

#4

Yes, pretty sure it’s a vacuum leak from the injectors. There’s a very loud hissing right above them on the driver’s side. I was leaning on the fuel rail pretty hard, and I was concerned something would break. I’ll try a dab of grease on each O ring.

Weird thing, when I removed the manifold I discovered one side had two gaskets stacked.

#5

Two gaskets thats odd. That couldnt have sealed very well. If its a vac leak from the injectors a spray of starter fluid in the area should show itself. Or if its just obvious there is no need.

Deffinitely look at the injector O ring if that is missing or not in its grove your going to get a nasty leak.