Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing
2008 Suzuki Swift +SECTION Circuit/System Testing
- Verify the following conditions do not exist:
- Vacuum hose splits, kinks, and incorrect connections
- Engine vacuum leaks
- Crankcase ventilation system for vacuum leaks
- Fuel pressure that is too low or too high-Refer to Fuel System Diagnosis .
- Contaminated fuel-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
- Restricted exhaust system-Refer to Restricted Exhaust .
- If you find any of the above conditions, repair as necessary.
- Ignition OFF, disconnect the spark plug wire from the misfiring cylinder.
- Install the J 26792 to the boot of a spark plug wire and ground.
- Attempt to start the engine and observe the J 26792
. The spark tester should spark.
- If there is no spark, test the spark plug wire for the correct resistance. Replace the spark plug wire if necessary. If the spark plug wire test normal, refer to Electronic Ignition (EI) System Diagnosis for diagnosis of the ignition coil.
- Ignition OFF, remove the spark plug from the misfiring cylinder. Verify the following conditions do not exist with the spark plug:
- Gas, coolant, or oil fouled
- Cracked, worn, incorrectly gapped
- If there is a condition with the spark plug, replace the spark plug.
- Exchange the suspected spark plug with another cylinder that is operating correctly.
- Engine running, observe the scan tool Misfire Current Counters. The misfire should not follow the spark plug exchange.
- If the misfire follows the spark plug, replace the spark plug.
- If all conditions test normal, test or inspect for the following:
- A lean or rich fuel injector-Refer to Fuel Injector Solenoid Coil Test
- An engine mechanical condition-Refer to Symptoms - Engine Mechanical
IMPORTANT:
An erratic or weak spark is considered a no spark condition.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.