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.
System Too Lean (High Air/Fuel Ratio)
Idle speed may be too high or too low. Engine speed may vary up and down. Disconnecting IAC does not help. May set Code 44.
"SCAN" and/or voltmeter will read an oxygen sensor output of less than .30 volt (300 millivolts). Check for low regulated fuel pressure, or water contaminated fuel. A lean exhaust with an oxygen sensor output fixed above .80 volt (800 millivolts) indicates a contaminated sensor, usually silicon. This may set a Code 45.
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.