Can anybody tell me off the top of their head what the vacuum line located on the intake manifold underneath the dynamic chamber does? It is located between the oil injectors. I took the engine apart a while ago and I don't remember what was connected to it. This is the only line in the area. Then engine is an 87 NA. I plugged it to prevent leaks but I want to make sure it is hooked up correctly.

Thanks,

 

exactly between the injectors? or in the proximity? it might be the boost sensor vac line.

 

It is actually between the fuel injectors right at the edge of the manifold where it meets the engine. I went outside an took a photo and will try to attach it. Again, I have no clue what this is for.

 

I had no luck attaching the photo. But the piece sits right below the fuel injectors under the dynamic chamber.

 

I had no luck attaching the photo. But the piece sits right below the fuel injectors under the dynamic chamber.

 

If it's the one I think it is (that makes a lot of sense, huh?), it goes to the middle nipple on the front of the throttle body (right below the big nipple, which goes to the oil metering vac lines)...This is an S4, anyway...

 

block it off. you dont need it. That is if we are thinking of the same thing

 

I don't know about blocking it off- doesn't it provide the injector air bleeds their reference pressure?

 

It's for the fuel injector air bleeds. They improve fuel atomisation, which has many benefits. Leave them connected.

 

And it's not a vacuum line...It's a fresh air line.

 

Thanks, I reconnected the hoses as they should be and the car runs and idles much better now. This has been my winter project. I bought the body for $300. and found an engine through ebay for $200. Installed the rebuild kit from Rotary Resources. I am glad I did this.

One last thing that I don't have a warm and fuzzy feeling about. How do you make sure the oil metering pump is working properly. I hope I did not put too much RTV on the front cover in way of the the feeder hole. I was careful not to do this but seeing how the RTV squeezed out when the cover was tightened, I would like to make sure I am getting a good oil supply.

 

Ever thought about going with premix?

There is a functional check for the OMP system in both the Haynes and the FSM...

 

Thanks I'll check the FSM on the test procedure. I have seen posts here regarding premix on this web site. It is an option. I need to get the car through emissions. Afterwards I may try it if the OMP does not appear to be Working. I also saw something about an adaptor that goes between the front cover and the pump with a separate oil supply tank. This sounds like a good idea because you could monitor consumption to determine how well the pump is working.