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.
1988 Chevrolet Sprint TurboFACTORY OEM SERVICE PROCEDURE
Oxygen (O2) Sensor Signal Check
- Remove ECM from instrument panel without disconnecting coupler. Connect coupler if disconnected. Warm engine to normal operating temperature and keep at idle.
- Connect voltmeter between terminal Nos. 10 (O2 sensor signal) and 9 (ground). If voltmeter indicator deflects between zero and .8 volts when engine speed varies from idle to 1500-2000 RPM, feedback system is operating properly.
- If voltmeter indicator remains at zero, check for O2 sensor lead wire disconnected, intake system leak, air/fuel ratio too lean, second air constantly sent to exhaust, voltmeter inner resistance too small, or faulty O2 sensor.
- If voltmeter does not deflect and indicates about .8 volts, check for engine not warmed up (choke operating), defective coolant temperature sensor, defective WOT microswitch, or disconnected mixture control solenoid lead wire.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no 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.