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.
1998 Buick Regal LSFACTORY OEM SERVICE PROCEDURE
Engine Performance (3.8L) DTCS
ENGINE PERFORMANCE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC | Description |
|---|---|
| P0101 | MAF System Performance |
| P0102 | MAF Sensor Circuit-Low Frequency |
| P0103 | MAF Sensor Circuit-High Frequency |
| P0107 | MAP Sensor Circuit-Low Voltage |
| P0108 | MAP Sensor Circuit-High Voltage |
| P0112 | IAT Sensor Circuit-Low Voltage |
| P0113 | IAT Sensor Signal Voltage High |
| P0117 | ECT Sensor Circuit Low Voltage |
| P0118 | ECT Sensor Signal High Voltage |
| P0121 | TP Sensor System Performance |
| P0122 | TP Sensor Circuit-Low Voltage |
| P0123 | TP Sensor Circuit-High Voltage |
| P0125 | ECT Excessive Time To Closed Loop |
| P0131 | HO2S Circuit Low Voltage-Sensor 1 |
| P0132 | HO2S Circuit High Voltage-Sensor 1 |
| P0133 | HO2S Slow Response-Sensor 1 |
| P0134 | HO2S Insufficient Activity-Sensor 1 |
| P0135 | HO2S Heater Circuit-Sensor 1 |
| P0137 | HO2S Circuit Voltage Low-Sensor 2 |
| P0138 | HO2S Circuit Voltage High-Sensor 2 |
| P0140 | HO2S Insufficient Activity-Sensor 2 |
| P0141 | HO2S Heater Circuit-Sensor 2 |
| P0171 | Fuel Trim System Lean |
| P0172 | Fuel Trim System Rich |
| P0201 | Injector No. 1 Control Circuit |
| P0202 | Injector No. 2 Control Circuit |
| P0203 | Injector No. 3 Control Circuit |
| P0204 | Injector No. 4 Control Circuit |
| P0205 | Injector No. 5 Control Circuit |
| P0206 | Injector No. 6 Control Circuit |
| P0230 | Fuel Pump Control Circuit |
| P0300 | Engine Misfire Detected |
| P0325 | Knock Sensor Module Circuit |
| P0327 | Knock Sensor Circuit-Bank 1 |
| P0332 | Knock Sensor Circuit-Bank 2 |
| P0336 | 18X Reference Signal Circuit |
| P0341 | CMP Sensor Circuit Performance |
| P0403 | EGR Solenoid Control Circuit |
| P0404 | EGR Valve Pintle Stuck Open |
| P0405 | EGR Pintle Position Sensor Circ. Low Voltage |
| P0420 | TWC System Low Efficiency |
| P0440 | EVAP System |
| P0442 | EVAP System-Small Leak Detected |
| P0446 | EVAP System Canister Vent Blocked |
| P0452 | Tank Pressure Sensor Circuit Fault-Low Voltage |
| P0453 | Tank Pressure Sensor Circuit Fault-High Voltage |
| P0506 | IAC System RPM Low |
| P0507 | IAC System RPM High |
| P0530 | A/C Refrigerant Pressure Sensor Circuit |
| P0560 | System Voltage |
| P0601 | PCM Memory |
| P0602 | PCM Not Programmed |
| P0705 | Trans. Range Switch Circuit |
| P0706 | Trans. Range Switch Performance |
| P1106 | MAP Sensor Circuit Intermittent High Voltage |
| P1107 | MAP Sensor Circuit Intermittent Low Voltage |
| P1111 | IAT Sensor Circuit Intermittent High Voltage |
| P1112 | IAT Sensor Circuit Intermittent Low Voltage |
| P1114 | ECT Sensor Circuit Intermittent Low Voltage |
| P1115 | ECT Sensor Circuit Intermittent High Voltage |
| P1121 | TP Sensor Intermittently High Voltage |
| P1133 | HO2S Insufficient Switching-Sensor 1 |
| P1134 | HO2S Transition Time Ratio-Sensor 1 |
| P1257 | Supercharger System Overboost |
| P1351 | IC Circuit Open |
| P1352 | By-Pass Line/Circuit Open |
| P1361 | IC Circuit Not Toggling |
| P1362 | By-Pass Circuit Shorted |
| P1374 | 3X Reference Circuit |
| P1380 | EBCM/EBTCM DTC Rough Road Data Unstable |
| P1381 | Misfire Detected, No EBCM/PCM/VCM Serial Data |
| P1404 | EGR Valve Pintle Stuck Open |
| P1441 | EVAP System Flow During Non-Purge |
| P1554 | Cruise Control Status Circuit |
| P1571 | TCS Desired Torque Circuit |
| P1573 | EBTCM/PCM Serial Data Circuit |
| P1602 | EBCM/EBTCM Serial Data Circuit |
| P1605 | HVAC Serial Data Circuit |
| P1610 | Standard Body Module Serial Data Circuit |
| P1626 | Loss Of Serial Communication W/Theft Deterrent Or Theft Deterrent System Fuel Enable Circuit |
| P1629 | Theft Deterrent Crank Signal Malfunction |
| P1630 | Theft Deterrent System-PCM In Learn Mode |
| P1631 | Theft Deterrent System-Password Incorrect |
| P1635 | 5-Volt Reference "A" Circuit |
| P1639 | 5-Volt Reference "B" Circuit |
| P1641 | A/C Relay Control Circuit |
| P1646 | Boost Control Solenoid Control Circuit |
| P1651 | Fan No. 1 Relay Control Circuit |
| P1652 | Fan No. 2 Relay Control Circuit |
| P1662 | Cruise Control Inhibit Control Circuit |
| P1665 | EVAP Vent Solenoid Control Circuit |
| P1667 | Fuel Pump PWM Control Circuit |
| P1671 | MIL Control Circuit |
| P1673 | Engine Hot Light Control Circuit |
| P1676 | EVAP Vent Solenoid Control Circuit |
| P1689 | TCS Delivered Torque Control Circuit |
Factory Service Tools
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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.