got a 85 13b, and when cold the car idles at 4k for about 2 min then drops to 800-1k rpm. once i get it going i find its running rich as can be. car has plenty of power and under 50%-100% thottle it runs like a bat out of hell, but below half thottle if you hold it at a cruise it surges every so often. any ideas?

 

Surging at cruise without abrupt changes in speed makes me think the cutch may be slipping.

 

Did the PO do mods to the fuel system? Like bigger injectors? The SE, as far as I know, is notorious for running rich as it has the high pressure system but not the neat-o manifold that they put into the 2nd gen.

 

I won't rule out the clutch but if I pull a hill it's fine. As for the injectors, this was happening before and I had a local injector rebuilder do them and he said theyre correct.