Christian Mello
Member
I picked up a 98 Volvo Autocar and it seemed to run well but was filthy. I cleaned it up a bit and found what looked to be a leaking gasket on the oil pump. I took it off, made a gasket and threw a bead of silicone around it, then I put it back. The leak was fixed but a check engine light came on. Code 121 (position sensor). It ran fine but i still needed to fix the check engine code. I replaced the position sensor (which is right behind the oil pump)with a new one and now not only is the code still on but it literally wont run. Its firing is all messed up. The plug looks fine. I cleaned it. I put the old sensor back in but it's still messed up. It's as if it's trying to run on 2 cylinders. Can anyone help me? Thanks.