Pulling my hair out (if I had any)!, Surging idle that won't go away Options

[mpoffers]

I've had this 75 1.8L 914 for nearly two years and I have yet to get a decent idle. When I first start the car it revs up to about 1800 rpms. After 30 seconds or so it dies. If I set the idle adjustment high enough I can get it ot to keep running, but even then it ALMOST dies, then surges up to 1500 or so, then cycles back and forth. With the idle set high it is reluctant to rev back down when I let off the throttle.

Other that that, it runs pretty well. It pulls strong as expected at all revs. It's fun to drive, but blipping the throttle gets really tedious in any sor of traffic. It even passed Oregon DEQ. The idle problem isn't as bad when the engine is hot, but it is still there.

Per advice from you guys, I did a valve adjustment, set the dwell, checked the timing, replaced fuel hoses, and replaced all the vacuum hoses. I replaced the gaskets on the oil filler (flat and o-ring). I tried spraying suspect connections with WD-40, but no of them caused a surge.

What's left to try? Can I start disconnecting and plugging things that aren't needed at idle (decel valve or emissions stuff) to try to narrow down the problem? I suppose I could take to A&P in Portland, but I hate to admit defeat.

[detoxcowboy]

generally a surgeing idle is too lean, richen your mixture until it stops surging, do so after the car has warmed upp 15 min. or so

[budman5201]

generally a surgeing idle is too lean, richen your mixture until it stops surging, do so after the car has warmed upp 15 min. or so

I agree. Recently even with my ez30r subaru engine I was doing an auto tune with my link computer and accidentally typed in a 18 fuel value where a 48 value should of been during idle on my map. The car surged lower went below that value on my fuel map until it hit a richer value and then did surging higher to lower trying to steady itself out. I bet that's what your computer is trying to do.
It's prob got a vacuum leak somewhere other than the hose connections and the computer is trying to compensate.

I agree, get her warmed up and use propane gas and u should get a general area from where it's coming from.

Hey can we see a few pics of your engine bay? Maybe after working on crap so long u don't see it. I've had u guys point me in the right direction a ton when I couldn't see or find anything.