So I swapped out my injectors today with a new set of RV 275s. I'm pleased with the performance boost and overall improvement in throttle response. 

My problem I'm having is that I have a plastic tube about 3/16"  in diameter that has come loose and I can't figure out where it goes. In the attached picture you can see that one end comes from what appears to be a check valve maybe. Can anyone help me identify what and where this tubing is and where the other end may attach. On a possible related note, my interior vents have stopped working and they worked fine yesterday. My AC is producing cold air but the vents won't open. Any help would be greatly appreciated.

It is likely a vacuum line, which would explain why you can't change your mode settings.  Without a vacuum source, the HVAC system will default to defrost mode.

 

Start at the vacuum pump location and follow the lines up to the firewall (near the top part of your photo).  You should be able to find the other disconnected part.

 

- John

Edited August 13, 20186 yr by Tractorman

Like T-Man says. It's a vac. line. Thats the end that connects to the pump.

Same thing happened to me when I installed my RV275 injectors.  The plastic hose came out of the rubber connector at the vacuum pump.   Be carful putting it back in that rubber is old and could tear like mine did then there is a vacuum leak and the vents are slow to respond.   I had to replace that rubber fitting with a short piece of rubber hose.  

Thanks for the quick response. So I assume that the vacuum pump is some where on that driver side near the brake master cylinder area?

1 hour ago, ljrustler said:

So I swapped out my injectors today with a new set of RV 275s

 

46 minutes ago, IBMobile said:

Same thing happened to me when I installed my RV275 injectors. 

 

So the vacuum line pops off when you install RV275 injectors.  Does this happen when you install other injectors?  I need to know because I have a set of RV275 injectors to install.

 

19 minutes ago, ljrustler said:

So I assume that the vacuum pump is some where on that driver side near the brake master cylinder area?

 

The vacuum pump is gear driven and is attached to the front gear cover just below the fuel injection pump.  The power steering pump is piggy-backed onto the vacuum pump.  Follow the power steering hose from the brake booster to the power steering pump which is attached to the back of the vacuum pump.

 

- John

1 minute ago, Tractorman said:

So the vacuum line pops off when you install RV275 injectors.  Does this happen when you install other injectors?  I need to know because I have a set of RV275 injectors to install.

No , it shouldn't have come off.  I was just flailing around under the hood and knocked it of.

Thanks for the help, I'll go check it out. It shouldn't have come off for me either, but I also was a little over zealous in my approach to the project.

It can get knocked off anytime you are playing around under the hood. 

29 minutes ago, Tractorman said:

 

 

So the vacuum line pops off when you install RV275 injectors.  Does this happen when you install other injectors?  I need to know because I have a set of RV275 injectors to install.

 

 

 

- John

It's not worth taking the chance. Send them back for some 7x10's  . 

That would be a good way to convince the wife why you need bigger injectors.

1 hour ago, dave110 said:

It's not worth taking the chance. Send them back for some 7x10's  . 

That would be a good way to convince the wife why you need bigger injectors.

 

Whew!  For awhile I thought I was being taken too seriously.  I ran your idea by my wife - she said, "Install the RV injectors!".  

 

I guess I will just have to risk the chance the vacuum hose will pop off.

 

- John

So I found the connector on the vacuum pump and I slid the tube back in. Now my air vents are working again. Thanks to all of you that pointed me in the right direction.

 

I'm still really happy with the new RV275 injectors. I took it for a drive today and power and throttle response has increased significantly and no smoke at all. One thing I noticed is that my fuel pressure has increased about 1/2 psi at both idle and WOT. Also, my WOT boost pressure has increased by about 1 1/2 psi.

 

Thanks again!