About 2 months ago I changed my spark plug and spark plug wires at ~150,000 miles and did an oil change simultaneously because my truck was bogging and idling weirdly. After that my truck was running like new. This week, my truck started idling rough occasionally and dips just under 1k rpm while the issue occurs. I do not have any problems with fuel economy or power output. My biggest suspicion is that it is a leaking vacuum line, however, I have not begun looking for the leak. Does anyone have any suggestions as to what is the most common area that it could be leaking? I would like some insight because I would like to knock this out in one afternoon and not turn this into an all-day affair of troubleshooting.

Thank you.

2007 3.0 liter

 

Do yourself a favor and buy a paint can smoke machine for $60 off ebay. Save you tons of headache doing it any other way. Also money if you pay a mechanic for a gasket change. The paint can ones put out a ton of smoke so don't worry about paying more money for a better one. I personally always clean the IACV first when I see a car with low idle/stalling. It simple fast and easy. It could be getting stuck from carbon when its going full open or closed. Could always be something more serious and a compression check is cheap and eliminates a ton of variables.

People are gonna need to know your car and engine also to give you hints on where the leak might be btw.

 

just edited it thanks for reminding me