Hi I've just bought an 07 wrx with a few engine mods, it's running almost 320 bhp and I tried to fit a hks sequential dump valve but as soon as I started her up she just ran like a pig, running far too rich, is there a way round this via remapping or it is worth saving the problems and throwing the BOV in the bin?! New to the forums so would appreciate the experts advice!

 

bin it or re map it go back to a standard recirc

 

Yeah I put the recirculating one straight back on so I think I may stick to that one, have you heard of these kind of problems before?

 

Yes mate

 

it shouldn't be instantly rich at idle unless your dump valve is buggered though. If it's leaking air in our out then the whole system will be trying to compensate for it.

with a MAF based tune there isn't much tuning around it you can do, air is being lost from the system any time the valve dumps and the ECU has no sensor to read that info so it can only go by the air the maf sensor has measured. Generally better quality valves won't give you as much of an issue so maybe you just got a bad valve?

 

Okay, well it was a fairly expensive hks sequential one but to be honest I'm not going to risk causing the car any damage so I'm just going to leave it, I've heard that cone air filters can give a good effect though, obviously nothing like a dump valve but aparently they sound good when the such I the air, any truth to this?

 

They can also suck in hot air and just be as bad as some dump valves, hks are generally one of the better dump valves so would double check it's genuine and plumbed in correctly