i just bought my 03 evo about 2 weeks ago. it has a hks evc 5 boost controler set at 20psi. sometimes only sometimes the bust surges. like it will hit 20 psi and violently go down and up from 20-15-20-15-20 psi. The needle on the boost gauge will just flick very rapadly from 15-20 miltiple times. i can really feel it when the car is accelerating. what can be the problem. why is the boost surging.

this does not happen all the time. but whats up??

 

please i need some answers?
maybe i have a boost leak??? but i can hit 20psi at like 3200 rpm all the time like nothing.

maybe the cheep stock plastic bov is not holding the boost??

 

your bush is surging
THATS NO GOOD

 

Yeah, that is pretty damn bad. Surging bush killed any many fine folk over the recent years.





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