2004 DAEWOO LACETTI Pressure valve

ENGINE CONTROLS 1F – 3
DAEWOO V–121 BL4
DTC P0562 System Voltage(Engine Side) Too
Low 1F–270. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0563 System Voltage(Engine Side) Too
High 1F–272. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0601 Engine Control Module Checksum
Error 1F–274. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0604 Engine Control Module Internal/External
RAM Error 1F–275. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0605 Engine Control Module INMVY Write
Error 1F–276. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0656 Fuel Level Gauge Circuit Fault 1F–277. .
DTC P1181 Variable Intake Manifold Solenoid
Low Voltage 1F–279. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1182 Variable Intake Manifold Solenoid
High Voltage 1F–281. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1230 Fuel Pump Relay Low Voltage
(1.4L DOHC) 1F–283. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1230 Fuel Pump Relay Low Voltage
(1.6L DOHC) 1F–286. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1231 Fuel Pump Relay High Voltage
(1.4L DOHC) 1F–289. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1231 Fuel Pump Relay High Voltage
(1.6L DOHC) 1F–292. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1320 Crankshaft Segment Period
Segment Adaptation At Limit 1F–295. . . . . . . . . . . .
DTC P1321 Crankshaft Segment Period Tooth
Error 1F–297. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1382 Rough Road Data Invalid
(NON ABS) 1F–299. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1382 Rough Road Data Invalid (ABS) 1F–302
DTC P1385 Rough Road Sensor Circuit Fault
(NON ABS) 1F–305. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1402 Exhaust Gas Recirculation
Blocked 1F–308. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1403 Exhaust Gas Recirculation Valve
Failure 1F–310. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1404 Exhaust Gas Recirculation Closed1F–313
DTC P1511 Idle Charge Actuator Circuit Fault 1F–316
DTC P1512 Idle Charge Actuator Mechanical
Error 1F–319. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1513 Idle Charge Actuator Functional
Error 1F–321. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1537 A/C Compressor Relay High
Voltage 1F–324. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1538 A/C Compressor Relay Low
Voltage 1F–326. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1610 Main Relay High Voltage
(1.4L DOCH) 1F–328. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1610 Main Relay High Voltage
(1.6L DOHC) 1F–330. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1611 Main Relay Low Voltage
(1.4L DOHC) 1F–332. . . . . . . . . . . . . . . . . . . . . . . . . . DTC P1611 Main Relay Low Voltage
(1.6L DOHC) 1F–334. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1628 Immobilizer No Successful
Communication 1F–336. . . . . . . . . . . . . . . . . . . . . . . .
DTC P1629 Immobilizer Wrong Computation 1F–338
DTC P1660 Malfunction Indicator Lamp (MIL)
High Voltage 1F–340. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1661 Malfunction Indicator Lamp (MIL)
Low Voltage 1F–342. . . . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLE CODE DIAGNOSIS (1.8L DOHC) 1F–344.
Clearing Trouble Codes 1F–344. . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Codes (1.8L DOHC) 1F–344. . . .
DTC P0106 Manifold Absolute Pressure
Rationality 1F–347. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0107 Manifold Absolut Pressure Low
Voltage 1F–349. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0108 Manifold Absolut Pressure High
Voltage 1F–352. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0112 Intake Air Temperature Low
Voltage 1F–355. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0113 Intake Air Temperature High
Voltage 1F–358. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0117 Engine Coolant Temperature Low
Voltage 1F–361. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0118 Engine Coolant Temperature High
Voltage 1F–363. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0122 Throttle Position Sensor Low
Voltage 1F–366. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0123 Throttle Position Sensor High
Voltage 1F–369. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0131 Front Heated Oxygen Sensor
(HO2S1) Low Voltage 1F–372. . . . . . . . . . . . . . . . . .
DTC P0132 Front Heated Oxygen Sensor
(HO2S1) High Voltage 1F–375. . . . . . . . . . . . . . . . . .
DTC P0133 Front Heated Oxygen Sensor
(HO2S1) Slow Response 1F–378. . . . . . . . . . . . . . .
DTC P0134 Front Heated Oxygen Sensor
(HO2S1) No Activity or Open 1F–382. . . . . . . . . . . .
DTC P0135 Front Heated Oxygen Sensor
(HO2S1) Heater Circuit Not Functioning 1F–385. . .
DTC P0137 Rear Heated Oxygen Sensor
(HO2S2) Low Voltage 1F–388. . . . . . . . . . . . . . . . . .
DTC P0138 Rear Heated Oxygen Sensor
(HO2S2) High Voltage 1F–391. . . . . . . . . . . . . . . . . .
DTC P0140 Rear Heated Oxygen Sensor
(HO2S2) No Activity or Open 1F–394. . . . . . . . . . . .
DTC P0141 Rear Heated Oxygen Sensor
(HO2S2) Heater Circuit Not Functioning 1F–397. . .
DTC P0171 Fuel Trim System Too Lean 1F–400. . . .
DTC P0172 Fuel Trim System Too Rich 1F–404. . . . .
DTC P0201 Injector 1 Circuit Fault 1F–408. . . . . . . . .
DTC P0202 Injector 2 Circuit Fault 1F–411. . . . . . . . .

1F – 4IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0203 Injector 3 Circuit Fault 1F–414. . . . . . . . .
DTC P0204 Injector 4 Circuit Fault 1F–417. . . . . . . . .
DTC P0300 Multiple Cylinder Misfire Detected 1F–421
DTC P0301 Cylinder 1 Misfire 1F–426. . . . . . . . . . . . .
DTC P0302 Cylinder 2 Misfire 1F–431. . . . . . . . . . . . .
DTC P0303 Cylinder 3 Misfire 1F–436. . . . . . . . . . . . .
DTC P0304 Cylinder 4 Misfire 1F–441. . . . . . . . . . . . .
DTC P0317 Rough Road Sensor Source Not
Detected 1F–445. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0325 Knock Sensor Internal
Malfunction 1F–447. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0327 Knock Sensor Circuit Fault 1F–449. . . . .
DTC P0336 58X Crank Position Extra/Missing
Pulses 1F–452. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0337 58X Crank Position Sensor No
Signal 1F–455. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0341 Camshaft Position Sensor
Rationality 1F–458. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0342 Camshaft Position Sensor No
Signal 1F–461. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0351 Ignition Control Circuit A Fault
(Cylinder 1 and 4) 1F–464. . . . . . . . . . . . . . . . . . . . . .
DTC P0352 Ignition Control Circuit B Fault
(Cylinder 2 and 3) 1F–466. . . . . . . . . . . . . . . . . . . . . .
DTC P0401 Exhaust Gas Recirculation Insufficient
Flow 1F–468. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0402 Exhaust Gas Recirculation Excessive
Flow 1F–470. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0404 Exhaust Gas Recirculation Open
Valve Position Error 1F–474. . . . . . . . . . . . . . . . . . . .
DTC P0405 Exhaust Gas Recirculation Pintle
Position Low Voltage 1F–478. . . . . . . . . . . . . . . . . . .
DTC P0406 Exhaust Gas Recirculation Pintle
Position High Voltage 1F–481. . . . . . . . . . . . . . . . . . .
DTC P0420 Catalyst Oxygen Sensor Low
Efficiency 1F–484. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0443 Evaporative Emission System Purge
Solenoid Control Circuit 1F–486. . . . . . . . . . . . . . . . .
DTC P0461 Fuel Level Struck 1F–489. . . . . . . . . . . . .
DTC P0462 Fuel Level Low Voltage 1F–492. . . . . . . .
DTC P0463 Fuel Level High Voltage 1F–495. . . . . . .
DTC P0502 Vehicle Speed Sensor No Signal
(Engine Side) 1F–498. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0506 Idle Speed RPM Lower Than Desired
Idle Speed 1F–501. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0507 Idle Speed RPM Higher Than Desired
Idle Speed 1F–504. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0532 A/C Pressure Sensor Low Voltage 1F–507
DTC P0533 A/C Pressure Sensor High
Voltage 1F–510. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DTC P0562 System Voltage Too Low
(Engine Side) 1F–513. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0563 System Voltage Too High
(Engine Side) 1F–515. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0601 ECM Checksum Fault
(Engine Side) 1F–517. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0602 ECM Reprogrom Error 1F–518. . . . . . . .
DTC P0607 Lower Power Counter Error 1F–519. . . .
DTC P0700 Transaxle Control Module
Malfunction 1F–520. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1106 Manifold Abosolute Pressure
Intermittent High Voltage 1F–522. . . . . . . . . . . . . . . .
DTC P1107 Manifold Abosolute Pressure
Intermittent Low Voltage 1F–524. . . . . . . . . . . . . . . .
DTC P1111 Intake Air Temperature Intermittent
High Voltage 1F–526. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1112 Intake Air Temperature Intermittent
Low Voltage 1F–529. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1114 Engine Coolant Temperature
Intermittent Low Voltage 1F–531. . . . . . . . . . . . . . . .
DTC P1115 Engine Coolant Temperature
Intermittent High Voltage 1F–533. . . . . . . . . . . . . . . .
DTC P1121 Throttle Position Sensor Intermittent
High Voltage 1F–535. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1122 Throttle Position Sensor Intermittent
Low Voltage 1F–537. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1133 Front Heated Oxyzen Sensor
(HO2S1) Too Few Transitions 1F–539. . . . . . . . . . .
DTC P1134 Front Heated Oxyzen Sensor
(HO2S1) Transitions Ratio 1F–543. . . . . . . . . . . . . .
DTC P1167 Front Heated Oxyzen Sensor
(HO2S1) Rich in Decel Fuel Cutoff (DFCO) 1F–546
DTC P1171 Fuel Trim System Lean During Power
Enrichment 1F–548. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1336 58X Crank Position Tooth Error Not
Learned 1F–550. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1391 G Sensor Rough Road Rationality 1F–552
DTC P1392 G Sensor Rough Low Voltage 1F–555. .
DTC P1393 G Sensor Rough High Voltage 1F–558. .
DTC P1396 ABS WSS Signal Variation 1F–561. . . . .
DTC P1397 ABS WSS No Signal 1F–563. . . . . . . . . .
DTC P1404 Exhaust Gas Recirculation Closed
Valve Pintle Error 1F–565. . . . . . . . . . . . . . . . . . . . . .
DTC P1601 SPI Communications Between
ECM and TCM 1F–568. . . . . . . . . . . . . . . . . . . . . . . .
DTC P1607 Lower Power Counter Reset 1F–569. . .
DTC P1626 Immobilizer No Response 1F–570. . . . . .
DTC P1631 Immobilizer Invalid Response 1F–571. .
DTC P1650 SPI Communications Between Error
with SIDM Chip 1F–572. . . . . . . . . . . . . . . . . . . . . . . .
DTC P1655 SPI Communications Between Error
with PSVI Chip 1F–573. . . . . . . . . . . . . . . . . . . . . . . .

ENGINE CONTROLS 1F – 5
DAEWOO V–121 BL4
SYMPTOM DIAGNOSIS1F–574 . . . . . . . . . . . . . . . . . . .
Important Preliminary Checks 1F–574. . . . . . . . . . . . .
Intermittents 1F–574. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hard Start 1F–576. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Surges or Chuggles 1F–579. . . . . . . . . . . . . . . . . . . . . .
Lack of Power, Sluggishness, or Sponginess 1F–581
Hesitation, Sag, Stumble 1F–583. . . . . . . . . . . . . . . . .
Cuts Out, Misses 1F–584. . . . . . . . . . . . . . . . . . . . . . . .
Poor Fuel Economy 1F–587. . . . . . . . . . . . . . . . . . . . . .
Rough, Unstable, or Incorrect Idle, Stalling 1F–588. .
Excessive Exhaust Emissions or Odors 1F–591. . . . .
Dieseling, Run–On 1F–592. . . . . . . . . . . . . . . . . . . . . . .
Backfire 1F–593. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR1F–594 . . . . . . . . . . . . .
ON–VEHICLE SERVICE 1F–594. . . . . . . . . . . . . . . . . . .
Fuel System Pressure Relief 1F–594. . . . . . . . . . . . . .
Fuel Tank 1F–594. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Pump 1F–596. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter 1F–597. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Rail and Injectors (1.4L/1.6L DOHC) 1F–598. . .
Fuel Rail and Injectors (1.8L DOHC) 1F–600. . . . . . .
Engine Coolant Temperature Sensor
(1.4L/1.6L DOHC) 1F–602. . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature Sensor
(1.8L DOHC) 1F–602. . . . . . . . . . . . . . . . . . . . . . . . . .
Throttle Position Sensor (1.8L DOHC) 1F–603. . . . . .
Throttle Body (1.4L/1.6L DOHC) 1F–603. . . . . . . . . . .
Throttle Body (1.8L DOHC) 1F–604. . . . . . . . . . . . . . .
Front Heated Oxygen Sensor (HO2S 1)
(1.4L/1.6L DOHC) 1F–606. . . . . . . . . . . . . . . . . . . . . .
Front Heated Oxygen Sensor (HO2S 1)
(1.8L DOHC) 1F–607. . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Heated Oxygen Sensor (HO2S 2) 1F–607. . . . .
Intake Air Temperature Sensor
(1.4L/1.6L DOHC) 1F–608. . . . . . . . . . . . . . . . . . . . . .
Intake Air Temperature Sensor (1.8L DOHC) 1F–609
Idle Air Control Valve (1.8L DOHC) 1F–609. . . . . . . . .
Manifold Absolute Pressure Sensor
(1.4L/1.6L DOHC) 1F–610. . . . . . . . . . . . . . . . . . . . . .
Manifold Absolute Pressure Sensor
(1.8L DOHC) 1F–611. . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Gas Recirculation Valve
(1.4L/1.6L DOHC) 1F–611. . . . . . . . . . . . . . . . . . . . . .
Exhaust Gas Recirculation Valve (1.8L DOHC) 1F–612
Knock Sensor (1.4L/1.6L DOHC) 1F–612. . . . . . . . . .
Knock Sensor (1.8L DOHC) 1F–613. . . . . . . . . . . . . . .
Evaporative Emission Canister 1F–614. . . . . . . . . . . . Evaporative Emission Canister Purge Solenoid Valve 1
F–615
Crankshaft Position (CKP) Sensor
(1.4L/1.6L DOHC) 1F–615. . . . . . . . . . . . . . . . . . . . . .
Crankshaft Position (CKP) Sensor
(1.8L DOHC) 1F–616. . . . . . . . . . . . . . . . . . . . . . . . . .
Camshaft Position Sensor (1.4L/1.6L DOHC) 1F–618
Camshaft Position Sensor (1.8L DOHC) 1F–619. . . .
Engine Control Module (1.4L/1.6L DOHC) 1F–620. . .
Engine Control Module (1.8L DOHC) 1F–621. . . . . . .
Electronic Ignition System Ignition Coil
(1.4L/1.6L DOHC) 1F–621. . . . . . . . . . . . . . . . . . . . . .
Electronic Ignition System Ignition Coil
(1.8L DOHC) 1F–622. . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION1F–623 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ignition System Operation 1F–623. . . . . . . . . . . . . . . .
Electronic Ignition System Ignition Coil 1F–623. . . . . .
Crankshaft Position Sensor 1F–623. . . . . . . . . . . . . . .
Camshaft Position Sensor 1F–623. . . . . . . . . . . . . . . .
Idle Air System Operation 1F–623. . . . . . . . . . . . . . . . .
Fuel Control System Operation 1F–623. . . . . . . . . . . .
Evaporative Emission Control System
Operation 1F–624. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evaporative Emission Canister 1F–625. . . . . . . . . . . .
Positive Crankcase Ventilation System
Operation 1F–625. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature Sensor 1F–625. . . . . . .
Throttle Position Sensor 1F–625. . . . . . . . . . . . . . . . . .
Catalyst Monitor Oxygen Sensors 1F–625. . . . . . . . . .
Exhaust Gas Recirculation Valve 1F–626. . . . . . . . . . .
Intake Air Temperature Sensor 1F–626. . . . . . . . . . . .
Idle Air Control Valve 1F–626. . . . . . . . . . . . . . . . . . . . .
Manifold Absolute Pressure Sensor 1F–626. . . . . . . .
Engine Control Module 1F–627. . . . . . . . . . . . . . . . . . .
Fuel Injector 1F–627. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knock Sensor 1F–627. . . . . . . . . . . . . . . . . . . . . . . . . . .
Rough Road Sensor 1F–627. . . . . . . . . . . . . . . . . . . . .
Strategy–Based Diagnostics 1F–628. . . . . . . . . . . . . .
EOBD Serviceability Issues 1F–628. . . . . . . . . . . . . . .
Serial Data Communications 1F–629. . . . . . . . . . . . . .
On–Board Diagnostic (EOBD) 1F–629. . . . . . . . . . . . .
Comprehensive Component Monitor Diagnostic
Operation 1F–630. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Common EOBD Terms 1F–630. . . . . . . . . . . . . . . . . . .
Reading Diagnostic Trouble Codes 1F–632. . . . . . . . .
Primary System–Based Diagnostics 1F–633. . . . . . . .

1F – 8IENGINE CONTROLS
DAEWOO V–121 BL4
EGR Desired Position
The desired exhaust gas recirculation (EGR) position is
the commanded EGR position. The ECM calculates the
desired EGR position. The higher the percentage, the lon-
ger the ECM is commanding the EGR valve ON.
Engine Load
Indicates engine load based on manifold absolute pres-
sure. The higher the percentage, the more load the engine
is under.
Engine Run Time
The engine run time is a measure of how long the engine
has been running. When the engine stops running, the tim-
er resets to zero.
Engine Speed
Engine Speed is computed by the ECM from the fuel con-
trol reference input. It should remain close to desired idle
under the various engine loads with the engine idling.
Fan
The Fan Control (FC) Relay is commanded by the ECM.
The FC Relay displays the command as ON or OFF.
Fuel Level Sensor
The Fuel Level Sensor monitors the fuel level in the tank.
The Fuel Level Sensor monitors the rate of change of the
air pressure in the EVAP system. Several of the Enhanced
EVAP System diagnostics are dependent upon the correct
fuel level.
Fuel System Status
The Closed Loop is displayed indicating that the ECM is
controlling the fuel delivery according to the Front Heated
Oxygen Sensor (HO2S1) voltage as close to an air/fuel ra-
tio of 14.7 to 1 as possible.
IAC Position
The scan tool displays the ECM command for the Idle Air
Control (IAC) pintle position in counts. The higher the
number of counts, the greater the commanded idle speed
reads. The Idle Air Control responds to changes in the en-
gine load in order to maintain the desired idle rpm.
Ignition 1 (Voltage)
The ignition volts represent the system voltage measured
by the ECM at the ignition feed circuit.
Intake Air Temperature
The ECM converts the resistance of the Intake Air Tem-
perature (IAT) sensor to degrees in the same manner as
the engine coolant temperature (ECT) sensor. In take air
temperature is used by the ECM to adjust fuel delivery and
spark timing according to incoming air density.Knock Present
The KS Noise Channel indicates when the ECM detects
the KS signal. The ECM should display NO at idle.
Long Term FT
The Long Term Fuel Trim (FT) is derived from the short
term fuel trim value. The Long Term FT is used for the long
term correction of the fuel delivery. A value of 128 counts
(0%) indicates that the fuel delivery requires no com-
pensation in order to maintain a 14.7:1 air to fuel ratio. A
value below 128 counts means that the fuel system is too
rich and the fuel delivery is being reduced. The ECM is de-
creasing the injector pulse width. A value above 128
counts indicates that a lean condition exists for which the
ECM is compensating.
MAP
The Manifold Absolute Pressure (MAP) sensor measures
the change in the intake manifold pressure which results
from engine load and speed changes. As the intake man-
ifold pressure increases, the air density in the intake also
increases and the additional fuel is required.
Misfire History #1–4
Indicates the number of misfires that have occurred after
195 current misfires have been counted. The current mis-
fire counter will add its misfires to the history misfire count-
er after 195 total misfires have taken place. If 1 cylinder is
misfiring, the misfiring current counter will have 195 mis-
fires counted before adding to its history counter. If 2 cylin-
ders are misfiring, the misfiring current counter will add to
their history counters after 97 misfires. The counter incre-
ments only after a misfire diagnostic trouble code (DTC)
has been set.
Front Heated Oxygen Sensor
The pre–converter Front Heated Oxygen Sensor
(HO2S1) reading represents the exhaust oxygen sensor
output voltage. This voltage will fluctuate constantly be-
tween 100 mv (lean exhaust) and 900 mv (rich exhaust)
when the system is operating in a Closed Loop.
Rear Heated Oxygen Sensor
The post–converter Rear Heated Oxygen Sensor
(HO2S2) represents the exhaust oxygen output voltage
past the catalytic converter. This voltage remains inactive,
or the voltage will appear lazy within a range of 100 mv
(lean exhaust) and 900 mv (rich exhaust) when operating
in a Closed Loop.
Short Term FT
The Short Term FT represents a short term correction to
fuel delivery by the ECM in response to the amount of time
the oxygen sensor voltage spends above or below the 450
mv threshold. If the oxygen sensor has mainly been below
450 mv, indicating a lean air/fuel mixture, short term fuel
trim will increase to tell the ECM to add fuel. If the oxygen
sensor voltage stays mainly above the threshold, the ECM
will reduce fuel delivery to compensate for the indicated
rich condition.

1F – 10IENGINE CONTROLS
DAEWOO V–121 BL4
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Camshaft Position Sensor Bolts (1.4L/1.6L DOHC)7–62
Camshaft Position Sensor Bolts (1.8 DOHC)8–71
Crankshaft Position Sensor Retaining Bolt (1.4L/1.6L DOHC)6.5–58
Crankshaft Position Sensor Retaining Bolt (1.8 DOHC)8–71
Electronic Ignition System Ignition Coil Retaining Bolts10–89
Exhaust Gas Recirculation Valve Retaining Bolts3022–
Engine Control Module Bolts12–106
Engine Coolant Temperature Sensor Bolt (1.4L/1.6L DOHC)17.513–
Engine Coolant Temperature Sensor Bolt (1.8 DOHC)2015–
Evaporative Emission Canister Flange Bolt4–35
Evaporative Emission Canister Purge Solenoid Bracket Bolt5–44
Fuel Filter Mounting Bracket Assembly Bolt4–35
Fuel Tank Retaining Bolts2015–
Fuel Rail Retaining Bolts2518–
Idle Air Control Valve Retaining Bolts (1.8 DOHC)3–27
Intake Air Temperature Sensor2216–
Knock Sensor Bolt2015–
Manifold Absolute Pressure Sensor Bolts (1.4L/1.6L DOHC)8–71
Manifold Absolute Pressure Sensor Bolts (1.8 DOHC)4–35
Oxygen Sensor Bolt4231–
Throttle Body Retaining Nuts (1.4L/1.6L DOHC)1511–
Throttle Body Retaining Nuts (1.8 DOHC)10–89
Throttle Position Sensor Retaining Bolts (1.8 DOHC)2–18

1F – 28IENGINE CONTROLS
DAEWOO V–121 BL4
COMPONENT LOCATOR
COMPONENT LOCATOR (1.4L/1.6L DOHC)
Components on ECM Harness
11. Engine Control Module (ECM)
12. Data Link Connector (DLC)
13. Malfunction Indicator Lamp (MIL)
14. ECM/ABS Harness Ground
15. Fuse Panel (2)
ECM Controlled Devices
20. Exhaust Gas Recirculation (EGR) Valve
21. Fuel Injector (4)
22. Main Throttle Idle Actuator (MTIA)
23. Fuel Pump Relay
24. Cooling Fan Relays (High)
25. Cooling Fan Control Relay (A/C Only)
26. Electronic Ignition System Ignition Coil
27. Evaporative Emission (EVAP) Control Purge Sole-
noid
28. Main Relay
29. A/C Compressor Relay30. Cooling Fan Relays (Low)
Information Sensors
31. Manifold Absolute Pressure (MAP) Sensor
32. Front Heated Oxygen Sensor (HO2S1)
33. Variable Geometry Induction System (VGIS) Sole-
noid
34. Engine Coolant Temperature (ECT) Sensor
35. Intake Air Temperature (IAT) Sensor
36. Vehicle Speed Sensor (VSS)
38. Crankshaft Position (CKP) Sensor
39. Knock Sensor
40. Rear Heated Oxygen Sensor (HO2S2)
41. Camshaft Position (CMP) Sensor
Not PCM/ECM Connected
42. Evaporative Emission Canister (under vehicle, be-
hind right rear wheel)
43. Engine Oil Pressure Switch
44. Air Cleaner

ENGINE CONTROLS 1F – 29
DAEWOO V–121 BL4
COMPONENT LOCATOR (1.8L DOHC)
Components on ECM Harness
11. Engine Control Module (ECM)
12. Data Link Connector (DLC)
13. Malfunction Indicator Lamp (MIL)
14. ECM/ABS Harness Ground
15. Fuse Panel (2)
ECM Controlled Devices
20. Exhaust Gas Recirculation (EGR) Valve
21. Fuel Injector (4)
22. Idle Air Control (IAC) Valve
23. Fuel Pump Relay
24. Cooling Fan Relays (High)
25. Cooling Fan Control Relay (A/C Only)
26. Electronic Ignition System Ignition Coil
27. Evaporative Emission (EVAP) Control Purge Sole-
noid
28. Main Relay
29. A/C Compressor Relay30. Cooling Fan Relays (Low)
Information Sensors
31. Manifold Absolute Pressure (MAP) Sensor
32. Front Heated Oxygen Sensor (HO2S1)
33. Throttle Position (TP) Sensor
34. Engine Coolant Temperature (ECT) Sensor
35. Intake Air Temperature (IAT) Sensor
36. Vehicle Speed Sensor (VSS)
38. Crankshaft Position (CKP) Sensor
39. Knock Sensor
40. Rear Heated Oxygen Sensor (HO2S2)
41. Camshaft Position (CMP) Sensor
Not PCM/ECM Connected
42. Evaporative Emission Canister (under vehicle, be-
hind right rear wheel)
43. Engine Oil Pressure Switch
44. Air Cleaner

1F – 36IENGINE CONTROLS
DAEWOO V–121 BL4
MULTIPLE ECM INFORMATION SENSOR DTCS SET
Circuit Description
The Engine Control Module (ECM) monitors various sen-
sors to determine engine operating conditions. The ECM
controls fuel delivery, spark advance, transaxle operation,
and emission control device operation based on the sen-
sor inputs.
The ECM provides a sensor ground to all of the sensors.
The ECM applies 5 volts through a pull–up resistor and
monitors the voltage present between the sensor and the
resistor to determine the status of the Engine Coolant
Temperature (ECT) sensor, the Intake Air Temperature
(IAT) sensor. The ECM provides the Exhaust Gas Recir-
culation (EGR) Pintle Position Sensor, the Throttle Posi-
tion (TP) sensor, the Manifold Absolute Pressure (MAP)
sensor, and the Fuel Tank Pressure Sensor with a 5 volt
reference and a sensor ground signal. The ECM monitors
the separate feedback signals from these sensors to de-
termine their operating status.
Diagnostic Aids
Be sure to inspect the ECM and the engine grounds for be-
ing secure and clean.
A short to voltage in one of the sensor circuits can cause
one or more of the following DTCs to be set: P0108,
P0113, P0118, P0123, P1106, P1111, P1115, P1121,
P0463, P0533.
If a sensor input circuit has been shorted to voltage, en-
sure that the sensor is not damaged. A damaged sensor
will continue to indicate a high or low voltage after the af-
fected circuit has been repaired. If the sensor has been
damaged, replace it.
An open in the sensor ground circuit between the ECM and
the splice will cause one or more of the following DTCs to
be set: P0107, P0108, P0113, P0118, P0122, P0123,
P1106, P1111, P1115, P1121, P0462, P0532.
A short to ground in the 5 volt reference circuit or an open
in the 5 volt reference circuit between the ECM and the
splice will cause one or more of the following DTCs to be
set: P0107, P0112, P0117, P0122, P1107, P1112, P1114,
P1122, P0462, P0532.Check for the following conditions:
S Inspect for a poor connection at the ECM. Inspect
harness connectors for backed–out terminals, im-
proper mating, broken locks, improperly formed or
damaged terminals, and poor terminal–to–wire con-
nection.
S Inspect the wiring harness for damage. If the har-
ness appears to be OK, observe an affected sen-
sor ’s displayed value on the scan tool with the igni-
tion ON and the engine OFF while moving
connectors and wiring harnesses related to the af-
fected sensors. A change in the affected sensor’s
displayed value will indicate the location of the fault.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Table.
1. The Powertrain On–Board Diagnostic (EOBD) Sys-
tem Check prompts the technician to complete
some basic checks and store the freeze frame and
failure records data on the scan tool if applicable.
This creates an electronic copy of the data taken
when the malfunction occurred. The information is
then stored on the scan tool for later reference.
9. A faulty EGR valve can leak a small amount of cur-
rent from the ignition feed circuit to the 5 volt refer-
ence circuit. If the problem does not exist with the
EGR valve disconnected, replace the EGR valve.
0. If a sensor input circuit has been shorted to voltage,
ensure that the sensor has not been damaged. A
damaged IAT or ECT sensor will continue to indi-
cate a high voltage or low temperature after the
affected circuit has been repaired. A damaged ACT,
TP, MAP, Fuel Tank Pressure, or EGR Pintle Posi-
tion sensor will indicate a high or low voltage or
may be stuck at a fixed value after the affected cir-
cuit has been repaired. If the sensor has been dam-
aged, replace it.
21. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.