[Shotimes] OT: Ford Probe GT Engine Issues

[Beisler Jonathon]

I am hoping that someone more knowledgeable than me might take pity and give
some advice.  Friend has a GT, 5spd that is not running well.  It idles very
rough and acts like it wants to stall but it doesn't.  It will drive but it
has no power.  It doesn't throw a check engine light.  But maybe the bulb is
out.  I haven't actually seen the car yet, I am just looking for some
pointers before I go over.  What could cause this and not throw some codes?
I know this is very vague, but any and all help would be appreciated.  Also,
can the codes be jumpered just like with our SHOs?
Thanks for any ideas.
JB