SR20DET looses boost past 4K
 

SR20DET drives fine but once past 4K it then looses power I can hit boost at lower RPM, 3500k, I do feel it pulling pass 4K, NOW when attempting again it doesn?t boost and starts to lag. Anyone experienced this ????


SpecR T28 OEM turbo

What did you change? Did you replace or modify something, THEN this problem started?

What have you tested? Compression? Fuel pressure? Power balance test? Vacuum / boost leaks?

I?ve checked spark plugs, checked side Mount intercooler, hoses are good. I still need to do a compression test.

The easy things to do are:

Check all your vacuum/boost lines. You could have a small crack or tear in one that opens up when it gets hotter.

Also, check your actuator- see if it's overly loose when moving it by hand- I've seen them get flaky with heat too.

Do you hear any hissing when trying to build boost but not boosting? Sure sign of a boost leak. Good luck!

EDIT: Just realized this is a week old. Would really be nice to hear back on what the fix was if found.

Mike