Rough idle after startup

[unitedracing]

So I've had the Vanagon on the road for a couple weeks and mostly all is good, however it's developed an issue I've never seen before. When starting cold or hot I get a rough idle AFTER the first couple seconds of running. It starts awesome cold or hot and will idle smooth initially... and then it gets rough. At first it would go away quickly but now it's taking longer. It could be an injector even though they're freshly rebuilt. I have a spare set I'll try this weekend to see if there's any change. Someone mentioned the fuel pressure regulator valve piston may be jammed. Any of you ever see this? Thanks!

[fatmobile]

 Do you have clear fuel lines?
Is there air in the fuel as you start?

[unitedracing]

Yes on the clear line, and there's no air showing. There's no smoke to speak of either. Its odd that it idles smooth for a few seconds and then gets rough.

[fatmobile]

Clear line to and from the pump?

[unitedracing]

I don't normally have one after pump, but did try that today.  No air seen. I did remove and check the pressure valve today and its fine. I have a spare set of injectors that I may throw in tomorrow to try. They are NA units, but nearly new. It will also give me a chance to have the current ones tested

[33B]

I've had rough idle after cold startup for a few seconds. It was the injectors not spraying right.