Think there a few factors affecting it right now.
The Bank Asya takeover has shown how this current government can pretty much do as they want, which must send warning signs to international investors. Exports are down by nearly 20%, tourism down by 8%, strikes in the vehicle manufacturing industry... even the contractors building the third bridge in Istanbul are verging on bankruptcy due to FX rates (USD in this instance).
Factor in an election, probably one of the most important in recent times, and its no wonder the markets are a bit shaky over the TL.
JF