The first thing I checked was the compression and it's 140PSI across the board so I figure there are no burned valves. I get a good, regular spark right at the plugs so don't think ignition is to blame. Irazor's problem seems the closest to mine but I would think that if there was a vacuum leak or lean condition of any kind, adding a little raw fuel down the intake should smooth it out wouldn't it? I'm still thinking the intake is cracked between the exhaust crossover passage and the intake runner to those two cylinders. I've just never seen it happen on that particular intake before. That would effect the fuel charge to those two cyinders and may effect the other two on that plane as well. The only thing keeping me from deciding "That's it!" is: time and effort for one....and somehow I would think I would get a backfire if the fuel was being burned in the intake runner before it got to the valves for those two cylinders. Maybe the timing is just right to prevent that but it just bothers me and gives me enough doubt that I may delay making a final decision until I get more info. Does anyone know what the smog reading would look like if exhaust gasses were getting mixed with the intake charge? Like an engine with a leaky or stuck EGR valve?
