All models cannot be serviced by replacing the oil pump, it has to be replaced as a unit in case there is a suspicion of a problem. With 1.4L engines, you will start by positioning the engine to No 1 cylinder at TDC and then take off the lower oil pan. Lift the edges of the coverinoil pump drive chain one by one until it is possible to pull it off. When reusing the oil pump drive chain doing so, use match marks and show the direction of travel. To remove the pump assembly, remove the mounting bolts of the oil pump, reposition the rear of the pump down, and pull the drive sprocket off of the chain. Removal of alignment sleeves in the upper oil pan has they not remained attached on the oil pump, the intake pipe fastener, and the oil pump seal/strainer. To install, line up the marks on the oil pump drive chain and crankshaft sprocket then insert the chain onto the sprocket. Fit a new oil pump seal/strainer, alignment sleeves and the oil pump assembly and tighten up the mounting bolts to the required torque. Install the lower oil pan, and add the oil then start the engine and inspect the oil pressure and any leakage. With 2.0L (CBPA) engines, these steps should be followed with, of course, the splash wall taken off, and match marks placed when reusing the oil pump drive chain. Once the assembly of the pump has been removed, fit the alignment sleeves and screw in the mounting bolts of the oil pump assembly. Lastly, with timing chain engines, two individuals are needed to take out the oil pump. Disassemble the oil baffle and, with a little help, draw back on the oil pump chain tensioner and fix it in position, and then take off the oil pump. Install a new O-ring on an oil pick-up tube, reinstall the tube and attach the retaining fastener. Once the oil pump is mounted on the chain, secure the retaining fasteners and a new oil baffle and reinstall the lower oil pan, pour oil in, turn on the engine, and inspect the leaks and gauge the oil pressure.