Intermittent starting trouble

[DannyBNH]

Typically the car with start right up, sit at around 1000 rpm for a bit, and then drop down to idle. This morning I went to start it up and it almost stalls.
It will go up to about 1000 RPM, then drop and sometimes dies. Other times it dances between about 400 and 1000 RPM, then eventually will flatten out.
It's been like this all day.

It drives absolutely fine otherwise.

I just finished up doing the fuel lines yesterday and am wondering if I have a loose connector or something. I put about 80 miles on it since putting on the new lines.

I also threw in a bottle of fuel injector cleaner this morning.
Where's a good place to start looking?
The car is a 84 US.

Thanks!
-Dan

[924CarreraGTP]

Check all of the fuel lines you replaced and check vacuum connections. You may have bumped one off or something. I had something like this in my '83 and somebody on here told me to check the vacuum lines. I went through the vacuum connectors and sprayed them with Armorall to swell them up and make them seal. At the same time I cleaned the connector to the warm up regulator and the thermo time switch. The car has run perfect since then though I'm not sure which procedure fixed it. I was having trouble with the car quitting in traffic too, but since it has run great.

[DannyBNH]

I ended up finding a broken vac line. It was like uncooked spagetti.
The other thing was the fuel line coming back from the cooler was crimping. Plan on replacing as soon as the rain goes away with a longer hose.