I recently remove the evaporator on my 1991 Civc hatchback (1.5 Dual point fuel injection) to replace the expansion valve. After I reinstalled the evaporator, my engine idles fine from a cold start, after about 3 minutes it starts a hunting or surging idle. I've read many of the posts about the possible causes of the surging idle. Can changing the evaporator cause the idle to surge?? I've changed the spark plugs, distributor, rotor, in process of changing all the vacuum lines, sprayed carb cleaner, etc. I had to move the EVAP cannister out of the way to get the coolant hoses off the evaporator. Could this cause it.

Thanks