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.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 83 (ENGINE CONTROLS - SELF-DIAGNOSTICS)DIAGNOSTIC TESTSDTC P0300: ENGINE MISFIRE DETECTEDDTC PARAMETERS
1999 GMC Forward Control 5.7 R, Automatic
DTC Parameters
1999 GMC Forward Control 5.7 R, AutomaticSECTION DTC Parameters
WARNING: This page is about a different car, the 2002 Saturn LW200, 2002 Saturn L200, and 2002 Saturn L100. However, it is still accessible from the selected car via links, so may be relevant.
- Sum of misfire counts are based on engine speed and load.
- Engine running for at least 5 seconds.
- Engine speed is 469-6400 RPM.
- ECT is 20-254°F (-7°C-123°C).
- Ignition voltage is 9-17 volts.
- Fuel level more than 10 percent.
- No CMP, CKP, ECT, fuel trim, IAT, idle speed, knock, MAP, HO2S1, TCC, TP, VSS, P0601, P1336 or P1621 DTCs are set.
DTC sets when a specific or random cylinder misfires have been detected after a series of 200 revolution tests.
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.