Idle acting up

[86suburbanNJ609]

Drove the truck to get some smokes and I noticed the idle is a lot slower and deeper sounding then usual almost like a big cam lol. Throttle response and start-up no problem or change on highway over 50 same thing fine. Its an edelbrock 1406 and mainly stock. I've only cleaned the outside of carb with 2+2. My question would could cause this? It doesn't stall or backfire almost like a lack of fuel?

 

[1987 GMC Jimmy]

Maybe your truck’s telling you to quit smoking. Just kidding. Sorta. Since it’s a new thing, I’d do a once over of the vacuum system. Speaking of which, a reading for that would be helpful. Timing and tuning are the first things that come to mind. Do you know what your timing is and roughly what your curb idle speed and idle mixture are set at? Also, your compressor clutch isn’t engaged, right?

 

[rt66paul]

A bad fan clutch can give you a roar, as can a dry cooling system.

 

[86suburbanNJ609]

No

Maybe your truck’s telling you to quit smoking. Just kidding. Sorta. Since it’s a new thing, I’d do a once over of the vacuum system. Speaking of which, a reading for that would be helpful. Timing and tuning are the first things that come to mind. Do you know what your timing is and roughly what your curb idle speed and idle mixture are set at? Also, your compressor clutch isn’t engaged, right?

No vacuum system hooked up and compresser off. I An going to clean the carb out and and readjust this weekend.