Remove your BCS. It only takes a 10mm wrench or socket. No need to remove the vac lines, just unbolt it so you can turn it and see the connector. Unhook the connector and read the resistance across the two pins on the BCS.
My 93 reads 28 ohms.
My 95 reads 30 ohms.
I have a bad one that reads 860k ohms, or nearly a megaohm.
What'* yours? If it reads like my two cars, you have a wiring problem OR the PCM is dumping boost for another detected reason. If it reads ALOT higher than my two cars, replace it.