heres my problem... I start my 98 SL1, it runs really hard. like its missing; and there is kinda sputtering from the exhaust. I have tried to isolate cylinders by pulling spark plug wires. no help they all seem to be running. I drive my car and as I accelerate through the gears it continues to miss. After a few miles I pull over and check it out under the hood. And I check the vaccum hoses and all is brand new anyway. By the time I get back in my car, engine runs great. No further problems. Until the engine has had a long time to cool down. Seems kinda crazy, because when It warms up, it really runs good. Would appreciate some help..