Hello can anyone suggest a way to diagnose a faulty turbo actuator? i think mine may be leaking/faulty, and at £100 for a replacement hks unit i dont wanna buy another one just on a hunch. at a guess, its probably been on the car over 10 years, i pulled the arm and the spring seems pretty tight but i dont know enough to be able to tell how it should be! Symptoms: (all slightly better once warmed up) bad throttle response (feels a bit like a boost leak) very little low down torque rapid turbo spool hesitant throughout the rev range unless flooring it (again like a boost leak) engine mods: hks actuator + upped boost bov delete fmic air filter exhaust ive checked: plugs + coilpacks afm boost pipes seem tight turbo itself seems ok (no smoke/oil consumption ect) just wanna get to the bottom of it now, would happily take it to a garage but theres no one local i cant trust. unless someone can recommend a good garage near southampton? thanks
Any ideas or constructive comments welcome!? is there any perishable components inside the actuator that could be faulty?
it's quite easy to test an actuator if you have access to a compressor with a variable pressure outlet. Takes all of 20min to do so consider going to a mates place who has one if you don't - Grab the compressor gun and add a ball inflation attachment, or some attachment to enable an airtight seal into normal 4mm hose - Remove vacuum line going to actuator from the boost source (normally the intercooler pipe) - Insert compressor gun into vacuum line (to simulate boost) - Set compressor to less than target boost and ensure arm does not move - Then set compressor to target boost and ensure it moves - If it doesn't move, keep increasing the compressor until the arm moves If you want to be even more accurate you can grab an extra couple bits of vacuum hose, a T piece fitting and a manual boost gauge to monitor pressure coming out of the gun. But setting it at the compressor is good enough in most instances Symptoms you describe point to possibly a leaking injector and/or vacuum leak. If you have access to a compressor then whip up a pressure tester as well - type "boost leak test" into youtube and learn up
