Feedback Carburetor Tests W/codes Chevrolet Camaro II

BASIC DIAGNOSIS & TESTING INFORMATION

Diagnosis of the CCC system is done in the following order

1. Ensure that all engine systems NOT related to the CCC are fully operational. DO NOT proceed with testing unless you are sure all other problems have been fixed.
2. Enter diagnostic mode and record trouble codes flashed by CHECK ENGINE" light. Exit diagnostic mode.
3. Distinguish between "hard" or "intermittent" trouble codes.
4. If trouble codes were displayed, go to Diagnostic Circuit Check chart. Follow instructions given there.
5. If no trouble codes were recorded, go to Drive Complaint Sheet and follow instructions given there.
6. After any repairs are made, perform System Performance Check. Clear any trouble codes.

Note. The following paragraphs explain the procedures involved in performing the steps outlined above.

The ECM stores component failure information for CCC system under a related trouble code which can be recalled for diagnosis and repair. When recalled, these codes will be displayed by flashes of CHECK ENGINE" lamp. Codes are displayed starting with lowest numbered code. Only codes in which a related malfunction has occurred will be displayed.

Note. Example of trouble codes is as follows: "FLASH", "FLASH", "FLASH", pause, "FLASH", "FLASH" followed by a longer pause identifies trouble code "32". First series of flashes indicates first digit of trouble code; second series of flashes indicates second digit of trouble code.

Scheme 60

1. Turn ignition on (engine off). "CHECK ENGINE" lamp should glow. Locate Assembly Line Data Link (ALDL) connector attached to ECM wiring harness under instrument panel. Insert spade lug terminal across "TEST" terminal and "GROUND" terminal. (Scheme 60) (Scheme 60): ALDL Connector Terminal Locations
2. "CHECK ENGINE" lamp should flash code "12". Code "12" consists of "FLASH", pause, "FLASH", "FLASH" followed by a longer pause. Trouble code "12" will be repeated 2 more times, then if any trouble codes are stored in ECM memory, they will be displayed in same manner.
3. Trouble codes will be displayed from lowest to highest numbered code (3 times each) and be repeated as long as the "TEST" terminal of ALDL connector is grounded.

CLEARING TROUBLE CODES

To clear memory of trouble codes, turn ignition on and ground TEST" lead at ALDL connector. Turn ignition off and remove ECM fuse from fuse block for 10 seconds. Remove "TEST" lead ground.

EXITING DIAGNOSTIC MODE

To exit diagnostic mode, turn ignition off and remove spade lug terminal from ALDL connector.

Note. The terms "enter diagnostics" and "exit diagnostics" will be used periodically throughout this section. Follow the procedure for entering diagnostic mode when instructed to "enter diagnostics". Follow the procedure for exiting diagnostic mode when instructed to "exit diagnostics".

FAILURE CODE DETERMINATION

During any diagnostic procedure, "hard failure" codes MUST be distinguished from "intermittent failure" codes. Diagnostic charts CANNOT be used to analyze "intermittent failure" codes, except as noted under Diagnostic Procedure. To determine "hard failure" codes and "intermittent failure" codes, proceed as follows

1. Turn ignition on and enter diagnostics. Read and record all stored trouble codes. Exit diagnostics and clear trouble codes. NOTE: Trouble codes will be recorded on "T" cars only with engine running. Turning ignition off after any trouble codes have been set will erase all codes.
2. Apply parking brake and place transmission in neutral (man. trans.) or "P" (auto. trans.). Block drive wheels. Start engine. "CHECK ENGINE" lamp should go out. Run warm engine at specified curb idle for 2 minutes and note "CHECK ENGINE" light. NOTE: Grounding "TEST" terminal with engine running will force engine to operate in closed loop mode if engine is warm and oxygen sensor is hot. If "CHECK ENGINE" lamp does not glow while in closed loop, CCC system is operating properly.
3. If "CHECK ENGINE" lamp comes on, enter diagnostics, read and record trouble codes. This will reveal "hard failure" codes. Codes "13", "15", "24", "35", "44", "45" and "55" may require road test to reset "hard failure" after trouble codes were cleared.
4. If "CHECK ENGINE" lamp does not come on, all stored trouble codes were "intermittent failures", except as noted under Diagnostic Procedure.

Note. Trouble code "15" malfunction will only display after 5 minutes of engine operation. Trouble code "12" will display only during time of no reference pulses received by ECM; it will never be stored as a malfunction.

DESCRIPTION

The CCC system should be considered as a possible source of trouble on engine performance, fuel economy and exhaust emission complaints ONLY after normal checks (which apply to a vehicle without CCC) have been performed.

Diagnosis of CCC system consists of 3 types of initial checks: Diagnostic Circuit Check, Driver Complaint Check and System Performance Check/Field Service Mode Check. Any of these checks may lead to a chart for locating source of problem or indicate no problem on that check and refer to another check.

If there is no trouble in CCC system, all 3 checks will result in that conclusion. The checks and their procedures are as follows

Note. If vehicle exhibits performance problems and no codes are set, refer to System Performance Chart (carbureted models)/Field Service Mode Check (EFI models). Components recorded by trouble codes generally do not cause performance problems when no codes are stored in ECM memory.

DIAGNOSTIC CIRCUIT CHECK

1. If complaint is "CHECK ENGINE" lamp related, this check will lead to most likely problem area, if malfunction exists. Enter diagnostics and record stored trouble codes. Begin diagnosis with lowest numbered code which is displayed and refer to appropriate trouble code chart.
2. If code "51" is displayed, refer to PROM removal and installation in this article for diagnosis of this code. If codes "54" or "55" are displayed with another code, always refer to diagnostic chart for code "54" or "55" first, then proceed to next lowest numbered code. NOTE: Any time codes "51", "54" or "55" are displayed with another code, start with "50-series" code first, then proceed to lowest numbered code.
3. If complaint is not "CHECK ENGINE" lamp related, this check will lead to most likely problem area. However, first make checks that would normally be made for the complaint on a vehicle without CCC system.
4. Follow instructions in diagnostic chart and repair malfunction. After repair, perform System Performance Check/Field Service Mode Check.

SYSTEM PERFORMANCE CHECK

1. This check verifies that CCC system is functioning correctly. This check should always be made after any repair on CCC system.
2. When performing this check, always engage parking brake and block DRIVE wheels. Parking brake on front-wheel drive models does not hold drive wheels. On engines equipped with Varajet carburetors E2SE Model), remove bowl vent line at carburetor and plug hose at carburetor during check and reconnect it after the check is complete.
3. On some engines, the oxygen sensor will cool off after only a short period of time while engine is idling. This will cause engine to go into open loop. To restore closed loop mode, run engine at part throttle several minutes and accelerate from idle to part throttle several times.

DIAGNOSTIC TOOLS

1. The CCC system does not require special tools for diagnosis. A dwell meter, tachometer, test light, ohmmeter, digital voltmeter with 10 megohms impedance (minimum), vacuum pump, vacuum gauge and 6 jumper wires 6" long (1 wire with female connectors at both ends; 1 wire with male connectors at both ends; 4 wires with male and female connectors at opposite ends) are only tools necessary for diagnosis.
2. A test light, rather than a voltmeter, must be used when indicated by diagnostic chart.
3. A dwell meter is used to measure the time that mixture control solenoid is on or off. This gives an indication of how the system is working and how rich or lean the mixture is. The dwell meter is set for 6-cylinder scale on ALL engines, regardless of how many cylinders the engine has.
4. Dwell meter is connected to Green connector located near the carburetor. This connector will not be connected to any circuit EXCEPT when you are testing with the dwell meter. DO NOT allow terminal wire to come in contact with any ground source, including rubber hoses. NOTE: If engine operation seems to change when dwell meter is connected to Green wire, remove dwell meter and use another type. A few brands are not compatible with CCC system.
5. When engine is at operating temperature and idling, dwell meter needle will move up and down on scale, between 10-50°. This indicates "Closed Loop" operation. If the needle does not move, "Open Loop" operation is indicated.

Location of CCC System Components. Scheme 61

TROUBLE CODE ID CHART

ECM TROUBLE CODE IDENTIFICATION

Flow Chart - System Performance Check Chart. Scheme 62

Flow Chart - System Performance Check Chart. Scheme 63

Flow Chart - Diagnostic Circuit Check Chart. Scheme 64

Flow Chart - Diagnostic Circuit Check Chart (1 OF 2). Scheme 65

Flow Chart - Diagnostic Circuit Check Chart (2 OF 2). Scheme 66

ENGINE PERFORMANCE PROBLEM - ODOR, SURGE, FUEL ECONOMY OR EMISSION PROBLEM

1. If the "CHECK ENGINE" light is not on, normal checks that would be performed on cars without the system should be done first.
2. If the alternator or coolant light is on with the "CHECK ENGINE" light, they should be diagnosed first.
3. Inspect for poor connections at coolant sensor, mixture control solenoid, etc. Also check for poor or loose vacuum hoses and connections. Repair as necessary.
4. If there is an intermittent "CHECK ENGINE" light, but no trouble code is stored, check the following: Check for intermittent connection in circuit between ignition coil to ground. Check for arcing at spark plug wires or spark plugs. Check battery to ECM terminals "C" and "R". Check ECM Terminals "A" and "U" to engine ground. Check for loss of trouble code long-term memory: Grounding dwell lead for 10 seconds with "TEST" lead ungrounded should produce a Code 23 which should be retained after the engine is turned off and the ignition switch is turned to "RUN" position. If a Code 23 is not displayed, ECM is defective and must be replaced. Ensure that the EST wires are kept away from the spark plug wires, distributor housing, ignition coil and alternator. Wires from ECM Terminal No. 13 to distributor and the shield (if used) should have a good ground.
5. If the customer is complaining of stalling, rough idle, dieseling or improper idle speed, see IDLE SPEED CONTROL CHECK.
6. If the complaint is detonation (spark knock) check the following items: Check the ESC system. Refer to ESC SYSTEM CHECK. Check the MAP or Vacuum Sensor output. See CHART 7: MAP SENSOR or CHART 8: VACUUM SENSOR. Check EGR system. Refer to EGR VALVE CHECK. Check TPS enrichment system operation. See TPS ENRICHMENT CHECK. Check HEI operation. Refer to appropriate IGNITION SYSTEM article in the ELECTRICAL section.
7. If the complaint is poor performance and/or poor fuel economy, check the following: Perform appropriate EST PERFORMANCE CHECK. Perform ESC SYSTEM CHECK.
8. If the customer is experiencing poor full throttle performance, refer to CRANKS, BUT WON'T RUN chart.
9. If the complaint is intermittent no starts, make the following checks: Check for incorrect pick-up coil or ignition coil. See CRANKS, BUT WON'T RUN chart. Check for intermittent ground connection on ECM.

ALL OTHER COMPLAINTS

For any other complaints, do the SYSTEM PERFORMANCE CHECK with engine warmed to normal operating temperature. Ensure all repairs have been made to vehicle before performing SYSTEM PERFORMANCE CHECK.

Chart 1: Dwell Fixed Under 10° Flow Chart (Lean Exhaust Indicated). Scheme 67

Chart 1: Dwell Fixed Under 10° Flow Chart (Lean Exhaust Indicated). Scheme 68

Chart 2: Dwell Fixed Between 10°-50° Flow Chart. Scheme 69

Chart 2: Dwell Fixed Between 10 & 50 Degrees Flow Chart. Scheme 70

Chart 3: Dwell Fixed Over 50° Flow Chart (Rich Exhaust Indicated). Scheme 71

Chart 3: Dwell Fixed Over 50 Degrees Flow Chart (Rich Exhaust Indicated). Scheme 72

Chart 4: TPS Enrichment Check Flow Chart. Scheme 73

Chart 4: TPS Enrichment Check Flow Chart. Scheme 74

Chart 5: "CHECK ENGINE" Light Inoperative Flow Chart. Scheme 75

Chart 5: "CHECK ENGINE" Light Inoperative Flow Chart. Scheme 76

CHART 6: WON'T FLASH CODE 12

REMOTE LAMP DRIVER IN HARNESS

Note. Check fuses that supply power to ECM. Repeat Diagnostic Circuit Check after any repair.

Chart 6: Won't Flash Code 12 Flow Chart. Scheme 77

Chart 6: Won't Flash Code 12 Flow Chart. Scheme 78

Chart 7: MAP & BARO Output Check Flow Chart. Scheme 79

Chart 7: MAP & BARO Output Check Flow Chart. Scheme 80

Chart 8: Vacuum Sensor Check Flow Chart. Scheme 81

Chart 8: Vacuum Sensor Check Flow Chart. Scheme 82

BARO & NON-TURBO MAP

TURBO MAP

Canister Purge Valve Check Flow Chart. Scheme 83

Canister Purge Valve Check Flow Chart. Scheme 84

Divert Valve Check Flow Chart. Scheme 85

Divert Valve Check Flow Chart 1 OF 2. Scheme 86

Divert Valve Check Flow Chart 2 OF 2. Scheme 87

WITH ELECTRIC AIR CONTROL & ELECTRIC SWITCHING VALVE

Note. Engines which use dual bed converters and electric air control valves (EAC/ES) (using vacuum for deceleration divert). On some applications, some air may divert to air cleaner above 2000 RPM. Make a visual inspection of hoses and connectors for leaks and proper connections. Repair as necessary.

AIR Management System Check Flow Chart. Scheme 88

Air Management System Check Flow Chart. Scheme 89

EFE (Electrically Heated) Check Flow Chart (3.8L Turbo). Scheme 90

EFE (Electrically Heated) Check Flow Chart (3.8L Turbo). Scheme 91

EFE (ELECTRICALLY HEATED) CHECK (EXCEPT 3.8L TURBO)

Note. An intermittent coolant sensor connection could cause the relay to click

EFE (Electrically Heated) Check Flow Chart (Except 3.8L Turbo). Scheme 92

EFE (Electrically Heated) Check Flow Chart (Except 3.8L Turbo). Scheme 93

EFE (Vacuum Servo) Check Flow Chart. Scheme 94

EFE (Vacuum Servo) Check Flow Chart. Scheme 95

EGR Valve Check Flow Chart. Scheme 96

EGR Valve Check Flow Chart. Scheme 97

Electric Diverter Valve Check Flow Chart. Scheme 98

Electric Diverter Valve Check Flow Chart. Scheme 99

ELECTRONIC SPARK CONTROL (ESC) SYSTEM CHECK

ENGINE KNOCK, POOR PERFORMANCE OR POOR ECONOMY (NO CODE 43)

Note. This chart should only be used after all other causes of spark knock have been checked, timing, EGR, MAP, engine temperature, excessive engine noise ect.

ESC System Check Flow Chart. Scheme 100

ESC System Check Flow Chart. Scheme 101

ENGINE CRANKS BUT WILL NOT RUN (WITH INTEGRAL COIL)

Note. Perform Diagnostic Circuit Check prior to this check. If a tachometer is connected to tachometer terminal, disconnect it prior to proceeding with this test. Intermittent no start may be caused by wrong pick-up or ignition coil.

Engine Cranks But Will Not Run Flow Chart (With Integral Coil). Scheme 102

Engine Cranks But Will Not Run Flow Chart 1 OF 2 (With Integral Coil). Scheme 103

Engine Cranks But Will Not Run Flow Chart 2 Of 2 (With Integral Coil). Scheme 104

ENGINE CRANKS BUT WILL NOT RUN (REMOTE COIL)

Note. Perform Diagnostic Circuit Check prior to this check. If a tachometer is connected to tachometer terminal, disconnect it prior to proceeding with this test.

Engine Cranks But Will Not Run Flow Chart (Remote Coil). Scheme 105

Engine Cranks But Will Not Run Flow Chart 1 Of 2 (Remote Coil). Scheme 106

Engine Cranks But Will Not Run Flow Chart 2 OF 2 (Remote Coil). Scheme 107

EST Performance Check Flow Chart (Except 5.0L VIN Y & 9). Scheme 108

EST Performance Check Flow Chart (Except 5.0L VIN Y & 9). Scheme 109

EST Performance Check Flow Chart (5.0L VIN Y & 9). Scheme 110

EST Performance Check Flow Chart 1 OF 2 (5.0L VIN Y & 9). Scheme 111

Idle Speed Control (ISC) Check Flow Chart. Scheme 112

Idle Speed Control (ISC) Check Flow Chart. Scheme 113

PULSAIR SOLENOID CHECK

Note. Make a physical check of connections and hoses first.

Pulsair Solenoid Check Flow Chart. Scheme 114

Pulsair Solenoid Check Flow Chart. Scheme 115

Pulse Width Modulated (PWM) EGR Check Flow Chart. Scheme 116

Pulse Width Modulated (PWM) EGR Check Flow Chart. Scheme 117

TCC Electrical Diagnosis Flow Chart. Scheme 118

TCC Electrical Diagnosis Flow Chart 1 OF 2. Scheme 119

TCC Electrical Diagnosis Flow Chart 2 OF 2. Scheme 120

Code 12: No Reference Pulses To ECM (Exc. 3.8L VIN "9") Flow Chart. Scheme 121

Code 12: No Reference Pulses To ECM (EXC. 3.8L VIN "9") Flow Chart. Scheme 122

Code 12: No Hall Effect Pulses (3.8L VIN "9") Flow Chart. Scheme 123

Code 12: No Hall Effect Pulses (3.8L VIN "9") Flow Chart. Scheme 124

Code 13: Open Oxygen Sensor Circuit Flow Chart. Scheme 125

Open Oxygen Sensor Circuit Flow Chart. Scheme 126

Code 14: Shorted Coolant Sensor Circuit Flow Chart. Scheme 127

Code 14: Shorted Coolant Sensor Circuit Flow Chart. Scheme 128

Code 15: Open Coolant Sensor Circuit Flow Chart. Scheme 129

Code 15: Open Coolant Sensor Circuit Flow Chart. Scheme 130

Code 21: Open TPS Circuit Or Misadjusted TPS Flow Chart. Scheme 131

Code 21: Open TPS Circuit Or Misadjusted TPS Flow Chart. Scheme 132

Code 23: Open Or Grounded M/C Solenoid Ckt Flow Chart. Scheme 133

Code 23: Open Or Grounded M/C Solenoid Ckt Flow Chart. Scheme 134

CHART 24: CODE 24: VEHICLE SPEED SENSOR (VSS) CKT

ECM TERM. 16 VOLTAGE CONSTANTLY HI OR LOW; BUFFER & VSS REMOTE FROM I.P. CLUSTER

Chart 24: Code 24: VSS Ckt Flow Chart. Scheme 135

Chart 24: Code 24: VSS Ckt Flow Chart. Scheme 136

CHART 24A: CODE 24: VEHICLE SPEED SENSOR (VSS) CKT ("A" & "J" SERIES)

ECM TERM. 16 VOLTAGE CONSTANTLY HI OR LOW; BUFFER & VSS ATTACHED TO I.P. CLUSTER ("A" & "J" SERIES)

Chart 24A: Code 24: VSS Ckt Flow Chart ("A" & "J" Series). Scheme 137

Chart 24A: Code 24: Vss Ckt Flow Chart ("A" & "J" Series). Scheme 138

CHART 24A: CODE 24: VEHICLE SPEED SENSOR (VSS) CKT ("A" & "F" SERIES)

ECM TERM. 16 VOLTAGE CONSTANTLY HI OR LOW; BUFFER & VSS ATTACHED TO I.P. CLUSTER ("A" & "F" SERIES)

Chart 24A: Code 24: VSS Ckt Flow Chart ("A" & "F" Series). Scheme 139

Chart 24A: Code 24: Vss Ckt Flow Chart ("A" & "F" Series). Scheme 140

Chart 24B: Park/Neutral (P/N) Ckt Flow Chart. Scheme 141

Chart 24B: Park/Neutral (P/N) Ckt Flow Chart. Scheme 142

Code 32: Baro Sensor Voltage Too Low Flow Chart. Scheme 143

Code 32: Baro Sensor Voltage Too Low Flow Chart. Scheme 144

BARO SENSOR

Code 33: Vacuum Sensor Ckt Voltage Too High Or Low Flow Chart. Scheme 145

Code 33: Vacuum Sensor Ckt Voltage Too High Or Low Flow Chart. Scheme 146

Code 34: (Turbo) Map Sensor Ckt Voltage Too High Or Low Flow Chart. Scheme 147

Code 34: (Non-Turbo) Map Sensor Ckt Voltage Too High Or Low Flow Chart. Scheme 148

Code 34: MAP Sensor Ckt Voltage Too High Or Low Flow Chart. Scheme 149

MAP SENSOR

Code 35: Shorted ISC Motor Throttle Switch Flow Chart. Scheme 150

Code 35: Shorted ISC Motor Throttle Switch Flow Chart. Scheme 151

Code 41: No Distributor Reference Signal Flow Chart. Scheme 152

Code 41: No Distributor Reference Signal Flow Chart. Scheme 153

Code 42: Bypass Or EST Problem Flow Chart. Scheme 154

Code 42: Bypass Or EST Problem Flow Chart. Scheme 155

Code 43: Voltage At ECM Terminal "L" Low Flow Chart. Scheme 156

Code 43: Voltage At ECM Terminal "L" Low Flow Chart. Scheme 157

Code 44: Lean Exhaust Indication Flow Chart. Scheme 158

Code 44: Lean Exhaust Indication Flow Chart. Scheme 159

Code 45: Rich Exhaust Indication Flow Chart. Scheme 160

Code 45: Rich Exhaust Indication Flow Chart. Scheme 161

CODE 51: PROM ERROR INDICATION

PROM is either installed incorrectly, defective, or the wrong part number. Check for proper installation and application. If installed properly, but code 51 is still present, PROM is defective and must be replaced.

Code 54: Constant High Voltage From M/C Solenoid To ECM Flow Chart. Scheme 162

Code 54: Constant High Voltage From M/C Solenoid To ECM Flow Chart. Scheme 163

Code 55: O2 Ckt Volt Hi Or Wrong, Volt On ECM Term. 21 Flow Chart. Scheme 164

Code 55: O2 Ckt Volt Hi Or Wrong, Volt On ECM Term. 21 Flow Chart. Scheme 165

CHART C1 - ECM REPLACEMENT CHECK CHART

In order to reduce incidents of repeat ECM failure, a revised ECM diagnostic procedure is available. Beginning in 1982, most ECMs are equipped with Integrated Circuits (IC) in place of separate transistors to operate various controlled components.

These ICs, called Quad-Drivers (QDR), have 4 separate outputs, meaning that each QDR can operate up to 4 different components. An inoperative QDR can result in ECM output becoming open or shorted to ground. Often, all 4 outputs of a QDR will fail, even if just one QDR circuit is faulty.

Refer to the following tables to determine which ECMs contain QDRs. Since this procedure is not applicable to ECMs which do not contain QDRs, those ECMs are not listed.

Performing the diagnostic flow chart will identify an inoperative QDR. Once the circuit is identified, it must be repaired to eliminate repeat ECM failure. This diagnostic procedure must be used when "Replace ECM" is the conclusion of any procedure.

ECM QDR IDENTIFICATION (CARBURETED)

Scheme 166

ELECTRONIC CONTROL MODULE (ECM)

Remove ECM mounting hardware. Disconnect electrical connectors and ground strap. Remove ECM. To install ECM, reverse removal procedure and ensure ground strap is securely attached.

Note. The ECM may be located at right side kick panel, glove compartment area or center console area.

Removal

1. Remove ECM as previously described. Remove sheet metal screw holding access cover closed and remove access cover. Using a small flat tip screwdriver, place blade at PROM carrier reference end between edge of opening in case and underside of protruding lip of carrier. Apply prying force and force side of carrier up as far as possible. Repeat procedure on other reference end lip.
2. Using prying force explained in step 1), force opposite end of carrier up as far as possible. Grasp carrier with thumb and forefinger. Gently rock carrier from side to side while applying upward force and remove PROM.

Scheme 167

1. Before installing new PROM, be sure part number agrees with removed PROM. Ensure molded "half-round" depression of PROM is at same end as "squared-off" symmetrical end of carrier and that PROM is centered in carrier. NOTE: If PROM is installed backwards and ignition is turned on, PROM will be destroyed and must be replaced. (Scheme 167): Replacing PROM in Electronic Control Module
2. Position carrier squarely over PROM socket with "squared-off" symmetrical end of carrier aligned with small notch in socket. Press down firmly on top of carrier and press down on body of PROM with narrow blunt tool. Squarely seat PROM in socket by alternately pressing down on either end of PROM.
3. Replace access cover and reinstall ECM. Reconnect electrical connectors and start engine. Enter diagnostics and check for trouble code "51". If trouble code "51" does not appear, PROM is correctly installed.
4. If code "51" does appear, PROM is not fully seated, is installed backwards, has bent pins, or is defective. Remove ECM and fully seat PROM. If pins are bent, remove PROM, straighten pins and reinstall PROM. If pins break or crack during straightening process, replace PROM. If PROM is installed backwards, replace PROM.

OXYGEN SENSOR

Raise and support vehicle (if required). Disconnect electrical connector at harness. Spray threads of oxygen sensor with penetrating oil and allow to soak for 5 minutes. Carefully remove oxygen sensor.

Note. DO NOT attempt to reinstall an oxygen sensor. Reinstallation of a sensor without special glass bead thread coating may require complete replacement of exhaust system.

THROTTLE POSITION SENSOR (TPS)

Removal and installation require removal of carburetor or throttle body unit.

MAP/BARO Or Vacuum Sensor Location (Location May Also Be In Passenger Compartment.). Scheme 168

TORQUE CONVERTER CLUTCH SOLENOID HIGH GEAR SWITCH

Removal requires disassembly of transmission.

Note. Removal and installation of any solenoids, switches or sensors not listed is accomplished by disconnecting the wiring harness and removing or detaching the device. To install, reverse removal procedure.

Pin Voltage Chart (3.8L - VIN A). Scheme 169

Pin Voltage Chart (5.0L - VIN Y & 9). Scheme 170

CCC System Wiring Diagram (Except Turbo & "J" Bodies). Scheme 171

CCC System Wiring Diagram (Turbo & Pontiac Sunbird/2000). Scheme 172