- Clogged fuel filter: Replace.
- Faulty fuel pump: Check fuel delivery pressure, replace if weak.
- Blocked or broken fuel injector: Inspect, clean or replace as needed.
Ignition system problems:
- Worn spark plugs: Check gaps, replace if needed.
- Faulty ignition coils: Test each one, replace failed coils.
- Damaged spark plug wires: Replace.
Air induction issues:
- Clogged air filter: Replace when visibly dirty.
- Loose or cracked hoses: Inspect rubber tubes for splits/damage, fix as needed.
Vacuum leaks:
- Cracked hoses, check all vacuum connectors; repair/replace.
EGR System Faults:
- Malfunctioning EGR valve; inspect, test vacuum supply, remove deposits, or replace.
Faulty Oxygen sensor; if sensor faulty, ECU cannot adjust its air-fuel mixture
Other factors to consider might include a faulty distributor cap/rotor(older ones may have these), timing alignment and compression issues(rare in Japanese engines like the 323's B6ZE unit) but the abovementioned ones are what cause such behavior in almost all vehicles.
