____________________________________________________________________________________
| Home / Car Engines / BMW Engines / BMW M20B23 |
BMW M20B23 Troubleshooting
| Engine starts up hard or won't start |
Gas tank is empty - Fill gasoline up.
Wrong grade of gasoline - Use correct gasoline grade.
Dirty fuel lines - Inspect and clean.
Spark plug wire is disconnected or loose - Inspect spark plug wiring connection, change or repair.
Spark plug is damaged - Spark plug need to be replaced.
Defective ignition - Check ignition and replace faulty components.
Plugged fuel filter - Install new filter.
Fuel lines are dirty - Fuel lines must be clean.
Clogged or damaged fuel pump - Clean or change fuel pump.
Dirty or damaged fuel injectors - Inspect fuel injectors and change as required.
Engine has low compression - Check cylinder block and replace defective parts.
| Unstable engine running |
Ignition system malfunction - Check ignition system and replace faulty parts.
Dirty air filter element - Replace or clean air filter.
Spark plug is damaged - Replace spark plug.
Fuel pump is defective or dirty - Test fuel pump and change if necessary.
Incorrect valve clearance - Adjustment procedure required.
Ignition timing is incorrect - Adjust ignition timing correctly.
Low idle speed setting is not correct - Correct idle settings.
| Engine starts but then stops |
Damaged spark plug - Spark plug need to be replaced.
Fuel injectors are faulty or clogged - Test fuel injectors and replace if necessary.
Faulty ignition coil - Replace ignition coil as necessary.
Valve springs are weak or broken - Install new valve springs.
Valves are stuck - Valves need to be cleaned.
| Engine is overheated |
Engine oil level is insufficient - Need to add engine oil.
Engine is under excessive load - Load reducing required.
Clogged fuel injectors - Inspect fuel injectors and service as required.
Ignition timing is wrong - Set the ignition timing properly.
Improper valve setting - Adjust valves as required.
Radiator core is clogged or radiator cap is leaking - Clean radiator or change cap.
Coolant level is low - Refill to the correct level and inspect system for leaks.
Thermostat is faulty - Install new thermostat.
Water pump failure - Water pump need to be replaced.
| Engine knocks or noises |
Stale fuel - Use correct fuel.
Engine is under excessive load - Reduce load.
Engine oil insufficient - Check oil level and add oil as required.
Incorrect low idle setting - Adjust the low idle speed.
Dirty or damaged fuel pump - Inspect fuel pump and change as required.
Crankshaft or main bearings wear - Install new parts as as required.
Valve clearance is improper - Adjust valve clearance.
Cylinder bore or piston rings are worn - Replace defective components.
| Engine loses power |
Fuel injectors are faulty or clogged - Check fuel injectors and change if required.
Air filter element is clogged - Clean or replace air filter.
Fuel pump is faulty or clogged - Inspect fuel pump and change as required.
Defective ignition - Check ignition system and replace faulty parts.
Defective cylinder head gasket - Replace the gasket as required.
Stuck or burned valves - Clean or replace valves.
Cylinder block components are faulty - Change defective components.
Plugged oil filter - Service or replace oil filter.
| High fuel consumption |
Dirty air filter element - Service or replace air filter.
Dirty or faulty fuel injectors - Clean or change fuel injectors.
Loose or defective spark plug - Tighten or change the spark plug.
Ignition timing is wrong - Adjust ignition timing correctly.
Valves are worn, stuck, or burned - Clean or replace valves.
Worn sleeve, rings, or piston - Replace faulty parts.
Excessive valve clearance - Adjustment procedure required.
Poor engine compression - Check cylinder block and replace damaged components.
| Engine oil consumption is too high |
Worn seals or gaskets - Replace worn parts to avoid leaks.
Valve guides and stems are worn - Change the valves.
Piston rings are stuck or worn - Piston rings replacement required.
Cylinder liner or piston is worn - Check liner and piston, install new components as required.
| Engine backfires |
Dirty fuel injectors - Test fuel injectors and service if necessary.
Restricted fuel lines - Fuel lines must be clean.
Wrong ignition timing - Adjust ignition timing correctly.
Improper valve setting - Adjust valves as required.
Clogged air filter - Clean or change air filter.
____________________________________________________________________________________