I am looking at buying an 05 mustang gt from a friend. He says that at random times the oil pressure drops really low and the car begins to idle rough. I'm wondering what can cause this. The car has 170k miles and has a manual trans. I was thinking that it might be the guage or the oil pressure sending unit, but if it were either of those, it wouldn't make the car run rough would it? He says that if it starts to run rough, all you have to do is hit the gas and bring the rpms up and the car will run fine again. Answers / suggestions / ideas please??