car running really rich after running high boost
 

Hi im new to Rx-7 club, this is my first time posting on here. I own a 87 turbo rx-7 with 200000km . the only modification done to my car is racing beat downpipe hooked up to stainless 3 inch exhaust with no cats.

the reason im posting is because after pinching the vacum line going to the wastgate on the turbo and hiting fuel cut, my car seems to be getting way to much fuel. The only way i can start my car is by turning of the fuel pump to start and then when the car starts running turn the fuel pump back on. this started happing after making acouple of high boost runs. I think my car only got about .8 bar of boost.
Any ideas anybody?