2008 tial bov
 

Hey guys havnt been on this site in a while but i have a 08 tc cobalt with the hahn racecraft super 20G turbo everything on the car is hahn BUT i have a tial q bov vent to atmosphere....i love the turbo set up and everything but my problem is when im city driving the afr's run rich as all hell and when i come to a stop the cars rpms will bounce between 400-1100 or 70% of the time stall out any idea why this could be? is it because of the bov but my question is ppl run atmosphere bov on my car and i havnt seen any problems with this or is it just a tuning issue? its just a pain in the ass having to restart my car and practicly every single stop or have the rpms bounce if it helps in that 70% i could be driving at say 40mph take my foot off the gas and cost and the afr's will be at 10 instead of 20 and thats also what the afr's are at when comming to a slow stop or city driving

I sounds like you have a vac leak.

Sounds like you're running a draw through MAF setup with the BOV vented to atmosphere. It's causing huge rich spikes which can bog the car. You may also have a massive vac leak but I bet the source is the BOV.

ok well my second question is how do i fix this?

One way would be to.buy new lower Co with a Mar relocate to the lower Cp instead of the Intake