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.
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HOMESERVICE MANUALSCHEVROLET1988R 20 P/U 2WD V8-454 7.4LREPAIR AND DIAGNOSISRELAYS AND MODULESRELAYS AND MODULES - POWERTRAIN MANAGEMENTRELAYS AND MODULES - COMPUTERS AND CONTROL SYSTEMSENGINE CONTROL MODULEDESCRIPTION AND OPERATIONMODES OF OPERATIONDECELERATION MODE
1988 Chevrolet R 20 P/U 2WD V8-454 7.4L
Deceleration Mode
1988 Chevrolet R 20 P/U 2WD V8-454 7.4LSECTION Deceleration Mode
In the Deceleration Mode, the ECM senses changes in throttle position and manifold pressure and reduces fuel delivery. When decelerating very rapidly, the ECM can cut off fuel completely for short periods of time.
RENDER: 1.0x
NO RELATED
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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.