Lnfmike

I have a 08 cobalt ss with ldk 6 speed swap. I was having low boost issues, found old coupler from stock charge pipe to turbo had a hole. Replaced with new one from zzp. I only have around 5lbs of boost and it comes slow. I checked all the couplers and they are tight. Intercooler is from zzp, stock one was replaced last year due to broken plastic ends. Any idea what it might be? Been working on it for a few days. Thanks.

Solaris99

I don't know about this car specifically, but if this were my old Audi A4 1.8T, I'd suspect the diverter/bypass valve.

USMCFieldMP

iTrader: (1)

Classic 1.8T issue.

63 Nova SS

iTrader: (3)

How does it sound when you let off? Is the diverter valve working ok? All charge pipes good? Crack in intercooler?

Solaris99

They didn't make those diaphragms for much over stock pressure. At least Audi had an upgraded OEM part. I think from the S4.

USMCFieldMP

iTrader: (1)

Sounds right; off of the 2.7T. I went with the 034 diverter on my 1.8T-swapped GTI... still have the stock unit in the TT though.