2.4L 4-CYLINDER Engine: Diagnosis Kia Optima I

TROUBLE SHOOTING

Note. To trouble shoot engine mechanical components, see ENGINE MECHANICAL in BASIC TROUBLE SHOOTING article in GENERAL INFORMATION.

Inspection

Inspect cylinder head for cracks damage and coolant leakage. Remove scale, sealing compound and carbon deposits. Clean all oil passages. Inspect cylinder head for warpage at deck surface. Resurface cylinder head if warpage exceeds specification. See CYLINDER HEAD table under ENGINE SPECIFICATIONS.

1. Check belt teeth for cracks, damage and oil contamination. Inspect sprockets for damage. Check tensioner pulley and idler pulley for grease leakage and roughness in rotation. Check sprockets and pulleys for wear, cracks or damage. Replace components if necessary.
2. Measure protrusion of auto tensioner rod. Auto tensioner rod should extend .55" (14 mm) from end of housing. Replace auto tensioner rod, if not within specification. Place tensioner in a soft-jaw vise, and test resistance of rod. If rod can be easily pushed in with light vise pressure, replace auto tensioner.

Inspect rotation of rocker arm roller. Inspect valve contact surface. Replace rocker arms as necessary. Inspect camshaft journal diameter and lobe height for wear. Replace camshaft if journal diameter and lobe height are not within specification. See CAMSHAFT table under ENGINE SPECIFICATIONS.

1. Check for foreign material between radiator fins.
2. Check the radiator fins for damage and straighten if necessary.
3. Check the radiator for corrosion, damage, rust or scale.
4. Check the radiator hoses for cracks, damage or deterioration.
5. Check the reserve tank for damage.
6. Check the automatic transaxle oil cooler hoses for cracking, damage or deterioration.

Place thermostat and thermometer in pan of water and heat. Heat water while observing thermometer. Thermostat valve should begin to open at 177-182°F (81-83°C). Thermostat should be fully open at 203°F (95°C).

Disassembly & Inspection

1. Check and clean oil holes, if clogged. Check counterbalance shaft front bearing area for wear or damage. If wear or damage is evident, replace front case.
2. If replacing bearing, use special tool to remove and replace right counterbalance shaft front bearing. Check counterbalance shaft journals for signs of wear. Counterbalance shaft (both shafts) rear bearing can also be removed and replaced with special remover tool. Check front case for cracks or other damage.
3. Replace oil seal if lip is worn or seal is otherwise damaged. If OIL PRESSURE light does not come on when ignition is turned on, check oil pressure switch, bulb and wiring. Oil pressure switch operating range is 2.1-4.3 psi (0.15-0.30 kg/cm 2 ).
4. Assemble oil pump gears into front case. Rotate pump and check for smooth operation. Ensure there is no ridge wear on contact surfaces. Check tip clearance between gear tips and front case.
5. Place straightedge across front cover housing. Measure side clearance between each gear and straightedge. Replace components if not within specification. See «OIL PUMP SPECIFICATIONS»(ref-121831-S15824501012001091100000) table.

OIL PUMP SPECIFICATIONS