ZEST BOLT Service Manual

Revotron 1.2T 12 2. Engine Idle Problems Condition Possible Cause Remedy Engine Starts but does not idle Faulty ETC unit. • Perform Diagnosis test. Replace as necessary. Clogged or faulty fuel regulator or pump. • Check fuel system components, repair or replace as necessary. Incorrect manifold absolute pressure (MAP) sensor signal input. • Check for leakage at sensor. • Perform diagnostic test. Engine idles erratically Disconnected or leaking vacuum line or vacuum leak at inlet manifold. • Inspect all vacuum lines and connections. Repair or replace as necessary. Faulty ETC unit. • Perform diagnostic test. Replace as necessary. Incorrect valve / ignition timing. • Check timing system components and repair or replace as necessary. Clogged or faulty fuel regulator or pump. • Check fuel system components, Repair or replace as necessary. Improper firing order. • Check ignition system and fuel. 3. Poor Engine Performance Condition Possible Cause Remedy Maximum RPM -low Insufficient battery voltage/charge - test battery and charging system. • Clean and tighten battery connections • Jump start engine. • Battery or charging system component faulty. Replace as necessary. Obstructed air filter or air inlet • Clean or replace air filter or inlet. Improper grade or contaminated fuel • Rush fuel system with fresh, clean, fuel of the correct type. Replace fuel filter. Faulty spark plugs, wires, or ignition coil • Check ignition system components for proper operation. Replace as necessary. Malfunctioning engine management system component • Perform engine management system diagnostic test as described in this section of the manual. Clogged or faulty fuel filter, fuel regulator, fuel line, or fuel pump • Check fuel system components, repair or replace as necessary. Incorrect crank angle signal • Check sensor gap and adjust to 1.4 ± 0.4mm Clogged or faulty fuel injector(s) • Check fuel injector operation. Replace as necessary. Improper firing order • Check ignition system and fuel injector connections. Rectify as necessary.