Can anyone point me in the right direction here to start diagnosing and hopefully fixing the idle issue with my truck. It is a 2003 4.2 with a 5 speed. Sometimes when cold after starting and running for a few minutes my idle speed will bounce up and down and it sounds like the engine is surging. I don't have a tach on my truck so i don't know where the idle is or what it is reving to but you can easily feel/hear the issue. Also the truck throws no code. I am planning on cleaning the TB and MAF this weekend, but I would love some ideas for other things to look at!

Thank you in advance!

 

IAC, Mass Air flow. Try those.

 

Add the IAC to cleaning the TB and MAF.