Anyone have any ideas of what else i should check?

It sounds like this vehicle is new to you, and I'd encourage you to perform a full tune-up as outlined in the schedule within your owners manual. Basically, complete every item on the service schedule unless you have records from the previous owner telling you that particular items have been done recently.

A few important items to mention: All filters (oil, air, fuel), Valve Adjustment (every 30,000 miles for the B280F V6 engine), Purge the old brake fluid (every 2 years), O2 Sensor, Coolant & Thermostat, Transmission Fluid and pan cleaning, Rear Differential Fluid, etc.

Also, it would be well worth your time to clean out the Idle Air Control Valve and the PCV system. Also check your Air Box Thermostat for proper operation (more info can be found here). I believe that the airbox thermostats that came with the B280 engines are adjustable (the base of the thermostat is threaded into a brass nut in the airbox) and you may be able to screw the thermostat farther down to compensate for a failure where it's open all the time. If you're drawing hot, preheated air into the intake all the time, you will notice a significant power loss. -not to mention a very short life span of your Air Mass Meter (and a replacement 006 AMM unit is hard to find on the used market).

Once you've completed a full tuneup on the car, it's a lot easier to troubleshoot problems (and you'll solve a lot of them in the process).

God bless,
Fitz Fitzgerald.
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'87 Blue 245, NA 237K