Sounds like you are running rich. Do you habe an aftermarket ignition? Typically that ends up as a distributor problem on the obd0 Tegs.
Test the fuel mixture (depending on the age of the plugs, they may not show much), the disty (more than likely the culprit), and then try lowering the fuel pressure a bit.
Other things to consider:
leaking injectors
fuel pump
main fuel relay
Plug wires
Good luck!