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.
Component Inspection
- Check PCV
- IG "OFF".
- Disconnect PCV.
- Check that PCV is properly operating.
- Is the PCV O.K?
YES
Go to "CHECK THE PCSV " procedure below.
NO
Substitute with a known - good PCV and check for proper operation.
If the problem is corrected, replace PCV and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
- Check the PCSV
- Ignition "OFF".
- Disconnect PCSV and Vacuum Hose.
- Apply vacuum on PCSV with Hand Vacuum Gauge.
- Is the PCSV keeping the Vacuum?
YES
Go to "CHECK INJECTOR " procedure below.
NO
Substitute with a known-good PCSV and check for proper operation.
If the problem is corrected, replace PCSV and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
- Check Injector
- Ignition "OFF".
- Remove Injector.
- Check Leakage and clog on Injector.
- Measure resistance terminal 1 and 2 of Injector connector (Component side).RESISTANCE SPECIFICATION
Coil Resistance (Ω) Temp (°C) Temp (°F) 1.25 20 68 - Is the measured resistance within specifications?
YES
Go to "CHECK SENSORS RELATED TO FUEL TRIM " procedure below.
NO
Substitute with a known-good Injector and check for proper operation.
If the problem is corrected, replace Injector and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
- Check Sensors related to Fuel Trim
- Check the Input Voltage of Sensors related to Fuel Trim (MAPS, TPS, ECTS, PCSV, Injector, and etc) - Refer to TROUBLESHOOTING .
- Are the sensors related to Fuel Trim O.K?
YES
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.