NoPistons -Mazda Rx7 & Rx8 Rotary Forum - 14 psi boost spike, ack!

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- - 14 psi boost spike, ack! (https://www.nopistons.com/3rd-generation-specific-18/14-psi-boost-spike-ack-68928/)

Hello all!

I've been getting a boost spike in 4th gear a freeway speeds, 60-75. It spikes to 14psi and will drop down to 10 faster than I can lift off the throttle. The car is a 1994 rx7 touring. I'm at 48k right now. The only other boost problem I had in the past is when the hose poped off the vacum tank. I've done a visual inspection from the top side of the car, and have not seen anything out of place. If there is anything I can check specifically, I am more than able, but I am still a relative rotary virgin.

Thanks!

I've done no mods to the car yet. Today I noticed that it does it in 5th gear too, and a lesser extent in 3rd gear, only up to 11.5 psi. Does anyone have any thoughts or ideas? Thanks!