I recived my fuel and ignition parts, replaced the old ones and was so happy that my engine was performing so much better. Lower mpg, better throttle respons, almost no jerking and more stabil idle.

Then I open my hood to check the oil and I see that I have forgotten to putt this tube back :



I put it back in place that night, and the next day the engine runs like crap again! I didn't put two and two togheter right there and then, but at some point i traced my steps and removed the tube again and the power is back, jerking is better, idle more steady and so on.


That leads me to think that my air filter is some way clogged. That little hole this tube leaves gives the engine more air. The filter is new last spring, and it dosen't look dirty. But I did put some compressed air through it some time last fall. This could have messed up the fibers.
I can see SOME light through it, but very little!

Any sense to this? Does this sound right? If so I have spent a lot of money on parts I might not need!