'03 Sport rough idle

[dakotanut]

I'm sure it won't be the basic stuff. Daughter told me it was running rough for about a week. Just curious what else it could be besides the filter, plugs, etc: Thanks for any and all help.

 

[arco777]

Pull codes if you are able; many auto parts stores will check them for free. Might give you some insight. Check for worn out spark plugs. Or, bad plug wires or boots that are arcing (engine running during hours of darkness makes this check easy). A fuel pressure test is always a good idea too.

 

[ReadLearn]

I'm brand new to this website and I'm having the same problem. Brand new plugs, wires, and boots. Mine was also pulling a code for throttle position sensor and picked one up from a junkyard and replaced it. Since we replaced tps no check engine light had come on. Could the tps from the junkyard be a possible cause for roughness?

 

[vroomzoomboom]

if its running rough until it warms up, and has hard starts, you may have bad upper intake gaskets (4L SOHC's are known to do that). the other problem may possibly be bad 02 sensors, but that usually throws a code.