I picked up this little 1600 DL Hatch about a month ago and have installed new CV's, a muffler, rebuilt the carb, and cleaned it up as best I can. After running for a couple minutes the rpm's like to jump up to about 2000 or more and once even up to 3500. Sometimes if I hit the gas it will go back down a bit but it still runs like crap the entire time. When I purchased it I checked all fluids and went over the essentials, and other than this running problem, it checked out fine. The other day I checked the oil and it turns out it has a bit of gas in it. Haven't changed the oil because I don't want to have it do the same thing again and be back where I started. I'm 90% sure its not the head gasket. It doesn't smoke other than a little puff on start up sometimes, the coolant is clean, and the oil isn't milky at all. The carb seems to be letting too much gas in, but the idle screw does absolutely nothing to change that and from what I can tell there is no separate fuel and air screws. I am totally stumped and would really appreciate any input or help if you're in the Portland area. I live in Wilsonville and would pay for your gas to come give it a once over if you think you'd be helpful.
I'll answer any questions to the best of my knowledge.
Thanks in advance all.