Lawn Dart

This summer, I bought a pretty beat '87 base model for $900. When I got it, at almost 150,000 miles, it purred like a kitten. Although, it did have the typical dip in power at 3750 rpm. Anyhow, after a few thousand miles, it started running rough. Sometimes, it would even stall. I noticed that fuel wasn't burning completely and gas mileage went way down to 10 mpg, so I theorized it to be an ignition problem. First, I changed the spark plugs. Good thing I did, because the electrodes on the leading plugs were almost gone. I also changed the oxygen sensor. The engine runs better, but it still stalls at red lights, bucks and runs bad on cold mornings. However, I found a strange way to make it run perfect. If I wind second gear all the way to 7800+ rpm and bounce off the limiter, (flooring it in neutral doesn't work) it runs perfect for the rest of the day. Has anyone experienced this before? Does anyone know what could be causing this problem?

Thanks,
Tony

Mushiki

Did you try adjusting the TPS?

Give this a read if you havent --
http://www.rotorwiki.com/index.php/TPS_Adjustment

Lawn Dart

Thank you for the advice.