Hi. I am new to this forum. I own a 1984 Toyota Celica GTS (California car). I had my fuel filter replaced (pain in the ass) by a mechanic. Afterwards, the oil pressure gauge was no longer working. There is oil in the car and the car ran fine. I suspect the sending unit may have been disconnected by accident while he was working on it. Do you guys know where this unit is? Isn't it usually on the engine block near the oil filter? Please help..