[sdhunter]

New (to me) 1994 Disco. The vacuum advance hose comes out of the plenum but is just cut off. I bought new hose tonight to put on tomorrow. The port (on the distributor) where I'm supposed put the hose actually has cap on it.... My guess is that the distributor was replaced at some point and the hose was never installed. The truck doesn't idle right when its warm. Likes to surge then drop to the point where it stalls. Would this unattached hose cause this? (vacuum leak, vacuum advance, etc.) Any thoughts would be helpful. Thanks in advance.

 

[p76rangie]

New (to me) 1994 Disco. The vacuum advance hose comes out of the plenum but is just cut off. I bought new hose tonight to put on tomorrow. The port (on the distributor) where I'm supposed put the hose actually has cap on it.... My guess is that the distributor was replaced at some point and the hose was never installed. The truck doesn't idle right when its warm. Likes to surge then drop to the point where it stalls. Would this unattached hose cause this? (vacuum leak, vacuum advance, etc.) Any thoughts would be helpful. Thanks in advance.

Some vacuum advances have two vacuum ports, one for a vacuum advance and one for a vacuum retard. The retard one is usually blocked off with a cap like you describe, so are you sure there is not another port that is either there or has been broken off.

 

[sdhunter]

There is another port on the back side of the vacuum advance that is capped as well.

 

[p76rangie]

There is another port on the back side of the vacuum advance that is capped as well.

You will need to take the distributor cap off, connect a hose to each port and such on it. Then see if they both do the same thing.