I was having problems logging in and had to use a different username/password. I posted using Mikesmith2 and asked a question about rough idle. To answer other readers questions the error code I got was P0171. The miles on my 2000 echo is 75,000 miles. It gets oil changes every 6 mnths, coolant changes every 2 yrs. and the transmission oil has been changed. I put seafoam in the tank and it started to idle rough, so I cleaned the Throttle Body, the MAF sensor, and replaced the plugs with Denso Iridiums. In plug 1 it was rusty and the coil sleeve was damp. It is still idling rough but improves when I clean the MAF but returns in a week. Any suggestions?