I've been having a long term issue with my car. After I had the car looked at by a "pro" (in May), it started to run a little rough at idle. I assumed it was just the new "normal". But after finishing my most recent project, I thought that sitting for 7 weeks+ was the issue.

So this weekend I checked vacuum lines and checked the plugs. The plugs were a little dirty but nothing bad. I checked the distributor and it was a little rough (so I cleaned it up). Obviously to get the distributor cap off, I had to remove the air filter box.

But in the process of putting things back together, I noticed that the air intake hose was completely missing. I think because it was not there when I started, I didn't even notice that it was gone. I cannot find it for the life of me (and haven't had a reason to take it off of the car in months).

So I'm guessing when I had the car looked at, the hose was not put back into the car (they must've taken off the air filter box).

I was looking at the bottom of the air filter box, and I noticed that there is a plug that goes into the vacuum line port. It wasn't plugged in and I knew that in order to remove the air filter box, I would have had to disconnect this plug. And if I hadn't disconnected this plug, it would've broken something. So I'm 100% certain I didn't remove it, and that it was not connected.


So I have a question. Would these issues potentially cause a rough idle?

Here is link to the plug I am talking about. It is on the bottom of the air filter box.




Here is the air intake I'm talking about (I found one at a pnp)



Sorry if this seems disjointed, I'm not sure what the names of the parts are.

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1985 245. 246K Gone..but not forgotten. Sold in 2013, found 2018! Still running on the road. Of course.