After my mods and tune, my car developed some driveability quirks that are starting to bug me.

My mod list is Helix 272 cams, cam gears, 880cc injectors, EVO 9 metal bypass valve (gus modded) HKS intake w/ buschur intake filter (replaced HKS filter with it) o2 housing, downpipe, test pipe and catback, Hallman MBC and injen IC pipes on stock 03 turbo

I live at 6500ft. The quirks that are bugging me have to do with off throttle and steady state throttle control.

When I'm climbing a grade holding the throttle steady, the boost will climb to 10 psi then the bov will flutter really rapidly nonstop. If I let off, then I get the usual PSSSSHHH, followed by a buck.

The other problem is off throttle, the engine will buck. Sometimes hard, sometimes soft. If I let off the throttle really fast, then the engine won't buck. I can't even drive this thing that fast through twisties from fear of bucking midcorner and messing up.

I'd like to know if you guys have experienced these things, and if there is a cure for them. It's hard to drive smooth with these problems. Thanks in advance.

 

get a diffrent bov or a non adjusted one and see if it helps sounds to me the bov is messed up

 

I have the same exact problem. You've either got to get on an off the throttle really fast or rreeeeeaaaallly slow. Does anyone know what the seat material is on the stock BOV/BPV? Any recommendations for a decent, but inexpensive BPV that fits the stock set-up?

 

Same problem here. The car only wants to drive 10/10ths, anything less and it bucks. I just don't get off the throttle in the turn. Brake in the straights but not too much, then coast through the turn and get on the throttle later without feathering it. Driving with this condition is harder, but it helped me brake later, keep my corner speed up, and get on the gas ASAP, without getting on it too early.