Hey everyone,

So the vacuum seems to be low on my engine (03 accord 2.4, auto trans) and I'm having idling issues. However I can't find any leaks so far (but yeah, there's a lot of lines!). I did run across this line on the passenger side that isn't connected to anything - but maybe it's intentional? It runs from the end of the fuel rail and down near the alternator, but it just ends there, I can't see anywhere obvious that it should be connected to. Does anyone know if it's supposed to be this way? I attached a couple of photos that show the hose origin and the end.

Thanks!


This is where it starts (it's the bottom line in the pic)

This is where it ends. Is it a drain/breathing line of some sort? Or where should it go?

 

I think that's the vacuum-control solenoid for the front engine mount. That mount is vacuum operated, to get soft when idling in-gear.

Anyway, one hose goes to a hose-barb on the back-side of the intake manifold just out of sight in your 2nd photo. (follow the dashed line way to the left in the drawing)


The other hose goes to the engine mount down low in the front.

 

That's super helpful- thanks! I'll take a look tonight at the back of the intake to see if I can spot the connection - I think that might be it, and embarrassingly enough it's probably my fault since I just replaced the positive battery cable recently.

 

(+) cable has the rubber boot in your 2nd photo, so it could have come off when you're working there. Disconnect the negative post at the battery because you don't want to short it when you're reaching in with tools & not enough room to see.

 

Thanks! It's pretty easy to spot once I'm looking on the right side of the intake, and that's what was disconnected - idle improved sitting in the driveway, so I'd say that solved it!

 

That would have been a pretty big vacuum leak when it was disconnected...