For 1990-2009 cars

#### Surges/Chuggles

Tests/inspections | Action
--- | ---
DEFINITION: Engine power variation under steady throttle or cruise. Feels like the vehicle speeds up and slows down with no change in the accelerator pedal position.
Preliminary |

• | Refer to Diagnostic System Check - Engine Controls .

• | Refer to Symptoms - Engine Controls .

• | Search for service bulletins.

• | Be sure the customer understands the transmission torque converter clutch, and the A/C compressor operation as explained in the owner's manual. Inform the customer how the TCC and the A/C clutch operate.

• | Verify that the PCM grounds are clean, tight, and in the correct locations.

Sensor/System |

• | Oxygen sensor (O2S 1): The O2S 1 should respond quickly to different throttle positions. If not, inspect the O2S 1 for silicon or other contaminants from fuel or the use of improper RTV sealant. The sensor may have a white powdery coating. Silicon contamination causes a high but false O2S 1 signal voltage (rich exhaust indication). The PCM will reduce the amount of fuel delivered to the engine, causing a severe driveability problem.

• | Test for correct operation of the manifold absolute pressure (MAP) sensor. Refer to DTC P0105 .

• | Test for the correct operation of the throttle position (TP) sensor. Refer to DTC P0105 .

• | Test for the correct operation of the engine coolant temperature (ECT) sensor. Refer to DTC P0117 and DTC P0118 .

Fuel System |

• | Test for the correct fuel pressure. Refer to Fuel System Diagnosis .

• | Test for contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

• | Inspect the fuel filter for restrictions.

• | Ensure that each fuel injector harness is connected to the correct fuel injector. Refer to

#### Power, Ground, and Injectors

Master Electrical Component List
Powertrain Control Module Description
Engine Data Sensors
Power, Ground, KS, CMP, CKP Coils, and ICM
OBD II Symbol Description Notice
G103 and G105
Compressor Controls
IGN SW-BATT2, WIPER, AIR BAG, TURN LPS, IGN MOD, BU LMP, PCM IGN, F/PINJR, A/C BFC, AUTO TRANS, ABS, IGN Fuses
.

• | Check any items which can cause an engine to run rich (long term fuel trim is significantly in the negative range). Refer to Diagnostic Aids for DTC P0172 .

• | Check any items that can cause an engine to run lean (long term fuel trim is significantly in the positive range). Refer to Diagnostic Aids for DTC P0171 .

Ignition System |

• | Test for the correct ignition voltage output with the J 36012-A spark plug jumper wires and J 26792 spark tester or equivalent.

• | Inspect the spark plugs for the following conditions:

- | Any moisture or fuel fouling

- | Any cracks

- | An incorrect gap

- | Any burnt electrodes or heavy deposits

• | If the spark plugs are fuel or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.

• | Inspect the ignition control module (ICM) for a correct ground connection.

• | Inspect the ignition coils for cracks or carbon tracking.

Additional |

• | Test for correct operation of the TCC. Refer to Road Test in Automatic Transaxle.

• | Inspect the exhaust system for following conditions:

- | Any damaged or collapsed pipes.

- | Any heat distress or internal failure of the muffler.

- | A plugged 3-way catalytic converter. Refer to Restricted Exhaust in Engine Exhaust.

• | Inspect the vacuum lines for kinks or leaks.

• | Test the generator output voltage. Refer to Diagnostic System Check - Engine Electrical in Engine Electrical.

If all procedures have been completed and no malfunctions have not been found, test and inspect all the connections within the suspected circuit and system.

Review the scan tool data. Refer to Scan Tool Data List .