THE BOX

I did check with brake cleaner and was spraying around but no idle change i could notice. I figured it would be a condition attributed to my BOV venting to atmosphere bleeding off metered air. I'm still interested in any input on the surging problem. it doesn't do it too often and doesn't seem to be connected to the blow off scenario. only seems to happen on longer trips and on the highway. I don't notice it happening when i have the cruse on just when I'm holding a steady speed with my foot like when I'm waiting to pass. Again any help is appreciated.

I have an 88 TSI with a few mods. I have a 1G BOV crushed down and 2.5 inch down pipe both have been installed for years. Im running 15 psi on a hallman mbc. I pulled the car out of storage this spring and it has a new habit. When i hold steady acceleration it sometimes has a small surge to it. It is pretty random which isn't to big of a problem but now anew issue has crept up. When i boost and let off the throttle right after to just coast the car stumbles and idles very low around 400 rpm. It will recover but it takes a few seconds. Just wondering what anyone thinks about it and what i could look at first. Thanks in advance for any help.