Post by
sjbsuperman1425 »
https://forums.nicoclub.com/sjbsuperman1425-u80456.html
Tue Aug 28, 2018 10:25 am
I have a S14 T28 BB turbo with stock wastegate actuator and recently I've been having issues with my boost pressure fluctuating, spiking, or just being lower than normal. I tested the boost controller (HKS EVC-S) and it functions properly. The solenoid works at specified settings and warning function works at set pressure. The issue I'm having is when I set the offset on the controller the other day, it was holding 10psi in all gears just fine. A day later, in hot/humid weather, it was working but after about 20 minutes of highway driving it started to drop 1-1.5psi. Now today, cooler/rainy, it is boosting 12psi or more. I understand it's not huge jumping numbers, but it just seems unstable and I'm pretty certain changes in weather shouldn't create that much of a change on boost pressure. I put pressure to the wastegate itself bypassing the controller solenoid and it moves feely and I didn't notice anything wrong there. Could the internal spring of the wastegate or the diaphragm be failing and causing these issues? I'm really stumped at this point and just looking for input.
Thanks guys.