86 pickup running rich

Hello everyone. I am new to this forum, and new to Nissans as well. I purchased a 1986 Hardbody and within 40 miles of driving, started having problems. The pickup has the 2.4 engine, and has 215k miles. Upon startup, the engine idles rough, and blows black smoke out the tailpipe. If I shut down the engine and look down into the throttlebody, I can see fuel puddling on the the throttle plate. Any ideas?

read the codes...

sounds like the injectors are sticking open..

Thanks for the ideas. I'll check the codes.
BlackBerry8310/4.2.2 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/102