Boost drops at high rpm's

[cbr900turbo]

I usually am pretty good with my dsm's but lately i havent had time to mess with some of them. I have a 92 colt with a 4g63. When you drive it it will make boost but as soon as it gets into the high rpms it just falls rapidly to nothing then you shift and it will make boost again. Everything is mostly stock i checked for leaks and cant seem to find any i replaced the bov and now im thinking wastegate/or turbo?

Any thoughts and help will be greatly appreciated.

Thanks,
Eric

 

[THEKID]

check the wastegate the spring is probably shot and its blowing open. I recently had a similar problem on a 2g that had a 20g on it. It kept blowing the gate open but it wasent the acuator it was the flapper. My advice is to check the actuator and flapper first.