I have a newly aquired 1987 rx7 T2. When I hit the gas at full throttle the turbo boost good but surges. It acts like it hits a rev limiter and then starts immediatly boosting again. I had this simmilar problem 8 years ago when I had my first T2 and I eliminated the problem by adding a fuel cut controller. But this time I would like to do it right. The car is stock except for a cone filter.

 

What are the modifications on the car, and what boost levels are you seeing?

 

Just a cone filter. All stock. It almost pegs the factoy boost gauge on full throttle.

 

That's FCD territory.

 

Do you guys think there might be a hidden vacumme leak
or maybe the wastegate is stuck?

 

Id check to see if the wastegate was stuck closed. Sound alot like boost/fuel cut to me.

 

Waste gates rarely give trouble, unless the clip comes off the end of the actuator rod.

Good guess on the vacuum leak.
The TID (turbo inlet duct) may have a crack that only pulls open with engine torque.

 

Is it ok to spray wd40 on the wastgate lever to free it or is there a few other tricks?

 

Should the wastegate lever be able to move freely
when it is pressed in by hand or is there a better way to
check this?

 

Hook up an air pump (even a bicycle pump will do)to the vacuum line going to the wastegate actuator. It should start to open with only a few psi. Do not pump too hard, I think the FSM warns not to go over 10psi, but its been a while since Ive read that section.