________________________________________________________________________________________
| Home / Car Engines / Toyota Engines / Toyota 5VZ-FE |
Toyota 5VZ-FE Troubleshooting
| Engine doesn't start or starts hard |
Gas tank is empty - Fill gasoline up.
Wrong grade of gasoline - Use correct gasoline grade.
Dirty fuel lines - Inspect and clean.
Defective spark plug wire connection - Inspect spark plug wiring connection, change or repair.
Defective spark plug - Change spark plug.
Defective ignition system - Check ignition and replace faulty components.
Plugged fuel filter - Fuel filter needs changing.
Clogged fuel lines - Fuel lines need to be cleaned.
Clogged or defective fuel pump - Clean or install new fuel pump.
Fuel injectors are defective or dirty - Clean or change fuel injectors.
Low cylinder compression - Check cylinder block and replace worn parts.
| Engine runs unevenly |
Ignition system problems - Inspect ignition system and change failed components.
Clogged air filter - Service or change air filter.
Defective spark plug - Install new spark plug.
Fuel pump is dirty or defective - Clean or replace fuel pump.
Valve clearance is not correct - Need to adjust valve clearance.
Ignition timing is incorrect - Ignition timing needs to be set properly.
Improperly adjusted low idle speed - Adjust the low idle speed.
| Engine starts but then stops |
Damaged spark plug - Change spark plug.
Clogged or damaged fuel injectors - Service or change fuel injectors.
Ignition coil is defective - Install a new ignition coil.
Worn or loose valve springs - Replace valve springs.
Valves sticking - Service the valves.
| Engine keeps overheating |
Not enough engine oil - Fill up the oil to required level.
Engine overloaded - Reduce engine load.
Fuel injectors are dirty - Test fuel injectors and clean if necessary.
Ignition timing is incorrect - Set the ignition timing correctly.
Incorrect valve setting - Set the valves properly.
Damaged radiator cap or dirty radiator core - Replace cap or clean radiator.
Coolant level is low - Fill the cooling system and check components for leaks or other faults.
Defective thermostat - Thermostat need to be replaced.
Water pump malfunction - Change water pump as required.
| Engine knocks or noises |
Stale gasoline - Use correct gasoline.
Engine is under excessive load - Reduce load.
Insufficient engine oil - Need to add engine oil.
Low idle speed setting is incorrect - Correct the settings.
Dirty or defective fuel pump - Test fuel pump and change if necessary.
Worn crankshaft or main bearings - Change or repair worn components.
Excessive valve clearance - Adjust valve clearance according to specifications.
Worn cylinder bore or piston rings - Change faulty components.
| Engine power is insufficient |
Fuel injectors are dirty or defective - Inspect fuel injectors and change as required.
Dirty air filter element - Change or service air filter.
Clogged or damaged fuel pump - Inspect fuel pump and change as required.
Defective ignition system - Check ignition and replace faulty components.
Damaged cylinder-head gasket - Change cylinder head gasket.
Valves are stuck or burned - Clean or change valves.
Cylinder block components are worn - Defective parts need to be replaced.
Dirty oil filter element - Replace or service oil filter.
| Engine uses too much fuel |
Dirty air filter element - Replace or clean air filter.
Clogged or defective fuel injectors - Service or change fuel injectors.
Spark plug is loose or faulty - Re-tighten or replace spark plug.
Improper ignition timing - Ignition timing needs to be set properly.
Valves are stuck, burned, or worn - Clean or change valves.
Sleeve, piston, or rings are damaged - Replace defective parts as required.
Excessive valve clearance - Adjust to proper valve clearance.
Poor compression - Inspect and replace wear parts.
| High oil consumption |
Damaged seals or gaskets - To repair leaks, replace worn parts.
Worn valve stems and valve guides - Need to replace the valves.
Worn or broken piston rings - Change the piston rings as required.
Cylinder liner or piston is scuffed - Check piston and liner, replace as required.
| Engine backfires |
Clogged fuel injectors - Service or replace fuel injectors.
Dirty fuel lines - Clean fuel lines.
Incorrect ignition timing - Ignition timing needs to be set properly.
Valve setting is wrong - Set the valves properly.
Plugged air filter - Clean or change air filter.
________________________________________________________________________________________
________________________________________________________________________________________
| Engines Technical Specifications |