You have a vacuum leak.  The increase and decrease
in idle speed it classic symptoms.
                                   Eric

MacLachlan, Bill wrote:

>listees:
>I have a rough idle  issue that I'll throw out for list consideration.
>The motor is an 1800 I-4,CIS. 50 degree
>new rotor, dist cap, leads and plugs.
>the idle is rough and tends to slowly increase then decrease.
>air and vacuum lines look good.
>Here's the item list wisdom may help me clean up before I take all the
>air and vacuum lines off.
>When the timing light is connected to #1 , there's a nice steady
>flashing- every time the plug fires. Same for #2&3.
>#4 cylinder is erratic. flashes regularly, then cuts out for a second or
>two , then back again. Has improved since I replaced rotor cap leads and
>put a new plug in, but its still not as consistent as #2&3.
>
>
>Bill MacLachlan
>Supervisor Bylaw Services
>Building Department
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