Re: 2004 Colorado rough idle
Depending on your mileage, you should think about changing the plugs. My 2005 started having rough idle last year, so I did the normal maintenace and replaced the plugs -- they were nasty at 87k miles.
05 Colorado Z85 LS Ext Cab (I5 M5) in Sunburst Orange :)
02 Honda VTX 1800C