Msp Running poor at idle and perfect in driving conditions.

[SlpMsp]

I tried looking for a similar thread for my problem and couldnt find one.
On my msp I have the following mods:

Hard Pipes/upgraded side mount
steedspeed exhaust manifold
corksport s-pipe/down pipe / stock catback
injen short ram
Afc split second on supermap stock running 8 psi

Now heres the problem, the car drives fine, cruising is around 15.1 afr and under wot between 11-12.3
Now when idling sometimes it stays perfect at 14.8 - 15.1 for 2 minutes and then jumps really poor to 17+ afr's for another 3-5 minutes and comes back down to a normal afr. It does this all the time back and forth.

I have no CEL besides the p171 that pops up time by time and then disappears.
My vaccum on my aem digital boost gauge reads -14.. and on my afc reads -21 under boost both read the same (thats weird)

Ive read a couple things that it could be maf related , iac , or maybe just need a better tune? is it really bad to run poor on idle?

Any help would be greatly appreciated!

 

[Mustard97]

it seems little low on vacuum at idle, i think your afc is broken, my car is at -22 at idle

 

[SlpMsp]

Thats what Im wondering is my wich one is faulty the gauge or the afc , im leaning towards the afc also . But Id be surprised that would be the cause of my problem

 

[hornsfan10609]

Sounds like there is a leak on the vacuum line for your boost gauge. I doubt it's the SSAFC, I have yet to hear of one fail.

 

[SlpMsp]

If there was a leak on my boost gauge vac line , wouldnt my vac reading on my afc be lower then -22 ?