Rough idle after interstate ride

[Bmatt12896]

Hello Everyone! I am new to this forum so if this issue has already been addressed, please forgive me. When I searched for the problem I'm having it yielded over 25k results so I figured this would be quicker. 

 

I own a 2005 Silverado 2500HD 6.0l 4x4 with a little over 107k miles. I purchased it at the end of April 2020. It started to have this issue about 2 months ago. After getting off the interstate, the motor idles rough almost to the point of stalling. I can put it in park, turn off the motor for about 10 seconds, and crank it back up and idles perfectly. My normal interstate ride is 6-7 miles. I set my cruise control at 79mph. I changed the plugs and wires 2 weeks ago. Anywhere else I drive, no issues. It only happens when I get off the interstate. Any help would be greatly appreciated.

[Jsdirt]

Check out the EGR valve - make sure it's not sticking in the open position when the problem occurs. That will dilute the mixture with too much exhaust at idle. Very common issue. 

[Colossus]

Did it do the same thing before the plugs and wires?  What kind of plugs did you use?   MAF is due to be cleaned as well if it has not been done so already, you can youtube how to do that with some non-residue leaving electrical contact cleaner.  How's the air filter?  clean the throttle body as well. 

[Bmatt12896]

44 minutes ago, Jsdirt said:

Check out the EGR valve - make sure it's not sticking in the open position when the problem occurs. That will dilute the mixture with too much exhaust at idle. Very common issue. 

Haven't thought of that yet. I'll check it out and report back. Thanks for the advice.

[Bmatt12896]

8 minutes ago, Colossus said:

Did it do the same thing before the plugs and wires?  What kind of plugs did you use?   MAF is due to be cleaned as well if it has not been done so already, you can youtube how to do that with some non-residue leaving electrical contact cleaner.  How's the air filter?  clean the throttle body as well. 

It was an issue before new plugs and wires. I added a CAI after the new plugs and wires and the throttle body looked good during the installation. MAF was also clean.

 

[CamGTP]

Trucks after 2001 do not have an EGR valve so you won't find that.

 

Do you have a handheld scanner that can report live data? I'd be curious as to what the o2 sensors are doing and how the long and short term fuel trims look.

[Jsdirt]

I thought it was '06? I can't keep up with the constant changes automakers do anymore. Frazzles my brain with just ONE model year ...