2007 Z-06 Issues

[Jimmy G.]

I have a low mile 2007 Z-06 that is running like dog poop. Is their a area where these engines tend to have issues, like coil packs, injectors, or computer issues?? It drives but not very well. Thought it was stale gas but after going to 'Low Fuel" twice and adding 2 gallons each time, I am convinced the gas is not an issue. Any advice from your history??

[Frank D.]

Re: 2007 Z-06 Issues

Don't virtually all American cars since 2001 have an OBDC port ? Get a scanner and see what codes it throws...
I personally like the Blue Driver: https://www.amazon.com/BlueDriver-Bl...4936257&sr=8-1

Not cheap but, its backed up by a cloud database that decodes any errors and reports back on the problem and typical things that fixed the issue for your SPECIFIC car. It works well for my fleet of cars...

[Rich G.]

[Ken R.]

Re: 2007 Z-06 Issues

https://www.corvetteforum.com/forums...her-issue.html
seems MAP sensor can do the rough engine from this post. See what codes it may be storing. Have fun.

[Mark E.]

Re: 2007 Z-06 Issues

Can you be more specific about the symptoms other than "running like dog poop"?

[Keith B.]

Re: 2007 Z-06 Issues

Don't virtually all American cars since 2001 have an OBDC port ? Get a scanner and see what codes it throws...
I personally like the Blue Driver: https://www.amazon.com/BlueDriver-Bl...4936257&sr=8-1

Not cheap but, its backed up by a cloud database that decodes any errors and reports back on the problem and typical things that fixed the issue for your SPECIFIC car. It works well for my fleet of cars...

since about 1980 any computer controlled engine management system had a port. By the early 90’s they got better

[Jimmy G.]

Re: 2007 Z-06 Issues

Runs very rough Kinda like a 427 with 2 crossed plug wires

[Jimmy G.]

Re: 2007 Z-06 Issues

Ordered a Scan Tool Thanks for all the advise Will reply when it is fixed (if it is)

[Gary J.]

Re: 2007 Z-06 Issues

Good thing you were not driving it on the Road Tour.

[John D.]

Re: 2007 Z-06 Issues

Some very general info from the service manual

Symptoms - Engine Controls
Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Symptoms DescriptionSymptoms cover conditions that are not covered DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause certain symptoms are listed separately under Additional Symptoms Test. Perform the Symptoms Testing before using the Additional Symptoms Tests. Poor Fuel Fill Quality test may be performed separately from the Symptoms Testing and Additional Symptoms Tests procedures.
Symptoms DefinitionBackfireFuel ignites in the intake manifold or in the exhaust system, making a loud popping noise.
Cuts Out, MissesA steady pulsation or jerking that follows engine speed, which is usually more pronounced as the engine load increases. This condition is not normally felt above 1500 RPM or 48 km/h (30 mph). The exhaust has a steady spitting sound at idle or at low speed.
Detonation/Spark KnockA mild to severe ping which usually occurs worse while under acceleration. The engine makes sharp metallic knocks that change with throttle opening.
Dieseling, Run-OnThe engine continues to run after the key is turned OFF, but runs very rough.
Hard StartEngine cranks OK, but does not start for a long time. The vehicle does eventually run, or may start but immediately stalls.
Hesitation, Sag, StumbleMomentary lack of response as the accelerator is pushed down. This condition can occur at any vehicle speed. This condition is usually more pronounced when first trying to make the vehicle move, as from a stop. This condition may cause the engine to stall in severe conditions.

Lack of Power, Sluggishness, or SponginessThe engine delivers less than expected power. Little or no increase in speed when the accelerator pedal is pushed down part way.

Poor Fuel EconomyFuel economy, as measured by an actual road test, is noticeably lower than expected. Also, the fuel economy is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.
Poor Fuel Fill QualityDifficulty when refueling the vehicle.

Rough, Unstable, or Incorrect Idle and StallingThe engine runs unevenly at idle. If severe, the engine or the vehicle may shake. Engine idle may vary in speed. Either condition may be severe enough to stall the engine.

Surges/ChugglesEngine power variation under steady throttle or cruise. Feels like the vehicle speeds up and slows down with no change in the accelerator pedal position.

Symptoms VerificationBefore using the Symptom tables, perform the following inspections:

• Ensure that the engine control module (ECM) and malfunction indicator lamp (MIL) are operating correctly.
• Ensure that there are no diagnostic trouble codes (DTCs) that are stored.
• Ensure that the scan tool data is within a normal operating range.
• Verify the customer concern.
• Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions
Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition:

Visual/Physical Check

• Ensure that the control module grounds are clean, tight, and correctly located. Refer to and .
• Ensure that the vacuum hoses are not split, kinked, and properly connected, as shown on the Vehicle Emission Control Information label. Refer to Emission Hose Routing Diagram. Refer to .
• Ensure that the air filter is clean and free from restrictions.
• Ensure that there is no water intrusion in connectors terminals and components.
• Inspect the air intake ducts for the following conditions:
  • Collapsed
  • Damaged areas
  • Looseness
  • Incorrect installation
  • Leaking
  
  
• Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
• Inspect the wiring harness for the following conditions:
  • Poor connections
  • Pinches
  • Cuts
  
  
• Inspect for loose, damaged, unseated, or missing sensors/components.
• Inspect the terminals for corrosion and correct contact.

Symptoms TestingBackfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

• Test for the following conditions:
  • The fuel system for the following:
    • Fuel System DiagnosisFuel Injector DiagnosisAlcohol/Contaminants-in-Fuel Diagnosis.
    
    
  • The ignition system for the following:
    • Spark Plug InspectionLoss of Coolant or Symptoms - Engine Mechanical.
    • Wet down the secondary ignition system with water from a spray bottle. Wetting down the secondary ignition system may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as the water is applied.
    • Weak spark using the J 26792Electronic Ignition System Diagnosis.
    Symptoms - Automatic TransmissionDTC P0171, P0172, P0174, or P0175.
  • Inspect the heated oxygen sensors (HO2S). The HO2S should respond quickly to different throttle positions.[COLOR=blue !important]Notice: Refer to Heated Oxygen and Oxygen Sensor Notice.

• • Water intrusion in the HO2S connector[COLOR=brown !important]Important: The embossed arrows on the mass air flow (MAF) sensor indicate the direction of the intake air flow. The arrows must point toward the engine.
    [/COLOR]
  • Inspect the MAF sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Install the MAF in the proper direction. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor ReplacementSymptoms - Engine Mechanical:Emission Hose Routing DiagramKnock Sensor System Description and DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333.
  • The exhaust system components for the following:
    • Physical damage or possible internal failure.
    • The three-way catalytic converters for a restriction.For more information, refer to Symptoms - Engine Exhaust.
    Crankcase Ventilation System Inspection/Diagnosis.
  • Evaporative emission (EVAP) canister purge solenoid that is stuck open
  • The engine cooling system for the following conditions:
    • The thermostat is the correct heat range. Refer to Thermostat DiagnosisCooling System Draining and Filling.
  
  
• If the above conditions do not address the symptom, refer to the additional symptoms tests.

Additional Symptoms TestsDetonation/Spark KnockTest the engine for an overheating condition. Refer to Symptoms - Engine Cooling.
Poor Fuel EconomyInspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.
Rough, Unstable, or Incorrect Idle and StallingInspect the engine mounts.
Surges/ChugglesTest the HO2S. The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The ECM reduces the amount of fuel delivered to the engine, causing a driveability condition.
Hard Start

• Temperature Versus Resistance for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the ECT circuits for a high resistance.
• Test the idle air control (IAC) system.
• Test the fuel pump relay operation. The fuel pump should turn ON for 2 seconds when the ignition is turned ON. Refer to Fuel Pump Electrical Circuit Diagnosis.

Hesitation, Sag, Stumble

• Test the manifold absolute pressure (MAP) sensor. Refer to DTC P0106.
• Test the generator. Refer to Symptoms - Engine Electrical. Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.

Poor Fuel Economy

• Heavy loads being carried or towed.
• Acceleration rate too much or too often.
• Inspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.

Poor Fuel Fill QualityTest for the following conditions that is applicable to the current symptom.
Difficult to fill

• Restricted vent lines
• The EVAP vent valve is stuck closed
• High fuel temperature
• A condition with the internal components of the fuel tank assembly.For more information, refer to:
• Fuel Hose/Pipes Routing Diagram
• Evaporative Emissions Hose Routing Diagram
• Evaporative Emission Control System Description

Fuel Odor

• Evaporative Emission Control System DescriptionFuel System Description.

[/COLOR]

[Tom L.]

Re: 2007 Z-06 Issues

Finding codes will be very useful. Be cautious if the code points to a part. I threw a P2138 in my 2013 GS, Accelerator pedal sensor issue, car was in limp mode and replaced the pedal. Not the problem. The root issue was simply a dirty connector in the engine compartment. Took it apart, sprayed it with electrical cleaner, put dielectric grease on the gasket only and put it together. Problem solved. Simple but annoying.

[Dick W.]

Re: 2007 Z-06 Issues

Some very general info from the service manual

Symptoms - Engine Controls
Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Symptoms DescriptionSymptoms cover conditions that are not covered DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause certain symptoms are listed separately under Additional Symptoms Test. Perform the Symptoms Testing before using the Additional Symptoms Tests. Poor Fuel Fill Quality test may be performed separately from the Symptoms Testing and Additional Symptoms Tests procedures.
Symptoms DefinitionBackfireFuel ignites in the intake manifold or in the exhaust system, making a loud popping noise.
Cuts Out, MissesA steady pulsation or jerking that follows engine speed, which is usually more pronounced as the engine load increases. This condition is not normally felt above 1500 RPM or 48 km/h (30 mph). The exhaust has a steady spitting sound at idle or at low speed.
Detonation/Spark KnockA mild to severe ping which usually occurs worse while under acceleration. The engine makes sharp metallic knocks that change with throttle opening.
Dieseling, Run-OnThe engine continues to run after the key is turned OFF, but runs very rough.
Hard StartEngine cranks OK, but does not start for a long time. The vehicle does eventually run, or may start but immediately stalls.
Hesitation, Sag, StumbleMomentary lack of response as the accelerator is pushed down. This condition can occur at any vehicle speed. This condition is usually more pronounced when first trying to make the vehicle move, as from a stop. This condition may cause the engine to stall in severe conditions.

Lack of Power, Sluggishness, or SponginessThe engine delivers less than expected power. Little or no increase in speed when the accelerator pedal is pushed down part way.

Poor Fuel EconomyFuel economy, as measured by an actual road test, is noticeably lower than expected. Also, the fuel economy is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.
Poor Fuel Fill QualityDifficulty when refueling the vehicle.

Rough, Unstable, or Incorrect Idle and StallingThe engine runs unevenly at idle. If severe, the engine or the vehicle may shake. Engine idle may vary in speed. Either condition may be severe enough to stall the engine.

Surges/ChugglesEngine power variation under steady throttle or cruise. Feels like the vehicle speeds up and slows down with no change in the accelerator pedal position.

Symptoms VerificationBefore using the Symptom tables, perform the following inspections:

• Ensure that the engine control module (ECM) and malfunction indicator lamp (MIL) are operating correctly.
• Ensure that there are no diagnostic trouble codes (DTCs) that are stored.
• Ensure that the scan tool data is within a normal operating range.
• Verify the customer concern.
• Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions
Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition:

Visual/Physical Check

• Ensure that the control module grounds are clean, tight, and correctly located. Refer to and .
• Ensure that the vacuum hoses are not split, kinked, and properly connected, as shown on the Vehicle Emission Control Information label. Refer to Emission Hose Routing Diagram. Refer to .
• Ensure that the air filter is clean and free from restrictions.
• Ensure that there is no water intrusion in connectors terminals and components.
• Inspect the air intake ducts for the following conditions:
  • Collapsed
  • Damaged areas
  • Looseness
  • Incorrect installation
  • Leaking
  
  
• Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
• Inspect the wiring harness for the following conditions:
  • Poor connections
  • Pinches
  • Cuts
  
  
• Inspect for loose, damaged, unseated, or missing sensors/components.
• Inspect the terminals for corrosion and correct contact.

Symptoms TestingBackfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

• Test for the following conditions:
  • The fuel system for the following:
    • Fuel System DiagnosisFuel Injector DiagnosisAlcohol/Contaminants-in-Fuel Diagnosis.
    
    
  • The ignition system for the following:
    • Spark Plug InspectionLoss of Coolant or Symptoms - Engine Mechanical.
    • Wet down the secondary ignition system with water from a spray bottle. Wetting down the secondary ignition system may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as the water is applied.
    • Weak spark using the J 26792Electronic Ignition System Diagnosis.
    Symptoms - Automatic TransmissionDTC P0171, P0172, P0174, or P0175.
  • Inspect the heated oxygen sensors (HO2S). The HO2S should respond quickly to different throttle positions.[COLOR=blue !important]Notice: Refer to Heated Oxygen and Oxygen Sensor Notice.

• • Water intrusion in the HO2S connector[COLOR=brown !important]Important: The embossed arrows on the mass air flow (MAF) sensor indicate the direction of the intake air flow. The arrows must point toward the engine.
    [/COLOR]
  • Inspect the MAF sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Install the MAF in the proper direction. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor ReplacementSymptoms - Engine Mechanical:Emission Hose Routing DiagramKnock Sensor System Description and DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333.
  • The exhaust system components for the following:
    • Physical damage or possible internal failure.
    • The three-way catalytic converters for a restriction.For more information, refer to Symptoms - Engine Exhaust.
    Crankcase Ventilation System Inspection/Diagnosis.
  • Evaporative emission (EVAP) canister purge solenoid that is stuck open
  • The engine cooling system for the following conditions:
    • The thermostat is the correct heat range. Refer to Thermostat DiagnosisCooling System Draining and Filling.
  
  
• If the above conditions do not address the symptom, refer to the additional symptoms tests.

Additional Symptoms TestsDetonation/Spark KnockTest the engine for an overheating condition. Refer to Symptoms - Engine Cooling.
Poor Fuel EconomyInspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.
Rough, Unstable, or Incorrect Idle and StallingInspect the engine mounts.
Surges/ChugglesTest the HO2S. The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The ECM reduces the amount of fuel delivered to the engine, causing a driveability condition.
Hard Start

• Temperature Versus Resistance for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the ECT circuits for a high resistance.
• Test the idle air control (IAC) system.
• Test the fuel pump relay operation. The fuel pump should turn ON for 2 seconds when the ignition is turned ON. Refer to Fuel Pump Electrical Circuit Diagnosis.

Hesitation, Sag, Stumble

• Test the manifold absolute pressure (MAP) sensor. Refer to DTC P0106.
• Test the generator. Refer to Symptoms - Engine Electrical. Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.

Poor Fuel Economy

• Heavy loads being carried or towed.
• Acceleration rate too much or too often.
• Inspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.

Poor Fuel Fill QualityTest for the following conditions that is applicable to the current symptom.
Difficult to fill

• Restricted vent lines
• The EVAP vent valve is stuck closed
• High fuel temperature
• A condition with the internal components of the fuel tank assembly.For more information, refer to:
• Fuel Hose/Pipes Routing Diagram
• Evaporative Emissions Hose Routing Diagram
• Evaporative Emission Control System Description

Fuel Odor

• Evaporative Emission Control System DescriptionFuel System Description.

[/COLOR]

You sir, are a life saver to the owners of newer cars. I will thank you for them.

[Jimmy G.]

Re: 2007 Z-06 Issues

Thanks

What a lot of information to start with.

Guess if I am going to keep the car I need to find a service manual

[Dick W.]

Re: 2007 Z-06 Issues

Some very general info from the service manual

Symptoms - Engine Controls
Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Symptoms DescriptionSymptoms cover conditions that are not covered DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause certain symptoms are listed separately under Additional Symptoms Test. Perform the Symptoms Testing before using the Additional Symptoms Tests. Poor Fuel Fill Quality test may be performed separately from the Symptoms Testing and Additional Symptoms Tests procedures.
Symptoms DefinitionBackfireFuel ignites in the intake manifold or in the exhaust system, making a loud popping noise.
Cuts Out, MissesA steady pulsation or jerking that follows engine speed, which is usually more pronounced as the engine load increases. This condition is not normally felt above 1500 RPM or 48 km/h (30 mph). The exhaust has a steady spitting sound at idle or at low speed.
Detonation/Spark KnockA mild to severe ping which usually occurs worse while under acceleration. The engine makes sharp metallic knocks that change with throttle opening.
Dieseling, Run-OnThe engine continues to run after the key is turned OFF, but runs very rough.
Hard StartEngine cranks OK, but does not start for a long time. The vehicle does eventually run, or may start but immediately stalls.
Hesitation, Sag, StumbleMomentary lack of response as the accelerator is pushed down. This condition can occur at any vehicle speed. This condition is usually more pronounced when first trying to make the vehicle move, as from a stop. This condition may cause the engine to stall in severe conditions.

Lack of Power, Sluggishness, or SponginessThe engine delivers less than expected power. Little or no increase in speed when the accelerator pedal is pushed down part way.

Poor Fuel EconomyFuel economy, as measured by an actual road test, is noticeably lower than expected. Also, the fuel economy is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.
Poor Fuel Fill QualityDifficulty when refueling the vehicle.

Rough, Unstable, or Incorrect Idle and StallingThe engine runs unevenly at idle. If severe, the engine or the vehicle may shake. Engine idle may vary in speed. Either condition may be severe enough to stall the engine.

Surges/ChugglesEngine power variation under steady throttle or cruise. Feels like the vehicle speeds up and slows down with no change in the accelerator pedal position.

Symptoms VerificationBefore using the Symptom tables, perform the following inspections:

• Ensure that the engine control module (ECM) and malfunction indicator lamp (MIL) are operating correctly.
• Ensure that there are no diagnostic trouble codes (DTCs) that are stored.
• Ensure that the scan tool data is within a normal operating range.
• Verify the customer concern.
• Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions
Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition:

Visual/Physical Check

• Ensure that the control module grounds are clean, tight, and correctly located. Refer to and .
• Ensure that the vacuum hoses are not split, kinked, and properly connected, as shown on the Vehicle Emission Control Information label. Refer to Emission Hose Routing Diagram. Refer to .
• Ensure that the air filter is clean and free from restrictions.
• Ensure that there is no water intrusion in connectors terminals and components.
• Inspect the air intake ducts for the following conditions:
  • Collapsed
  • Damaged areas
  • Looseness
  • Incorrect installation
  • Leaking
  
  
• Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
• Inspect the wiring harness for the following conditions:
  • Poor connections
  • Pinches
  • Cuts
  
  
• Inspect for loose, damaged, unseated, or missing sensors/components.
• Inspect the terminals for corrosion and correct contact.

Symptoms TestingBackfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

• Test for the following conditions:
  • The fuel system for the following:
    • Fuel System DiagnosisFuel Injector DiagnosisAlcohol/Contaminants-in-Fuel Diagnosis.
    
    
  • The ignition system for the following:
    • Spark Plug InspectionLoss of Coolant or Symptoms - Engine Mechanical.
    • Wet down the secondary ignition system with water from a spray bottle. Wetting down the secondary ignition system may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as the water is applied.
    • Weak spark using the J 26792Electronic Ignition System Diagnosis.
    Symptoms - Automatic TransmissionDTC P0171, P0172, P0174, or P0175.
  • Inspect the heated oxygen sensors (HO2S). The HO2S should respond quickly to different throttle positions.[COLOR=blue !important]Notice: Refer to Heated Oxygen and Oxygen Sensor Notice.

• • Water intrusion in the HO2S connector[COLOR=brown !important]Important: The embossed arrows on the mass air flow (MAF) sensor indicate the direction of the intake air flow. The arrows must point toward the engine.
    [/COLOR]
  • Inspect the MAF sensor installation. A MAF sensor that is incorrectly installed may cause a hard start. Install the MAF in the proper direction. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor ReplacementSymptoms - Engine Mechanical:Emission Hose Routing DiagramKnock Sensor System Description and DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333.
  • The exhaust system components for the following:
    • Physical damage or possible internal failure.
    • The three-way catalytic converters for a restriction.For more information, refer to Symptoms - Engine Exhaust.
    Crankcase Ventilation System Inspection/Diagnosis.
  • Evaporative emission (EVAP) canister purge solenoid that is stuck open
  • The engine cooling system for the following conditions:
    • The thermostat is the correct heat range. Refer to Thermostat DiagnosisCooling System Draining and Filling.
  
  
• If the above conditions do not address the symptom, refer to the additional symptoms tests.

Additional Symptoms TestsDetonation/Spark KnockTest the engine for an overheating condition. Refer to Symptoms - Engine Cooling.
Poor Fuel EconomyInspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.
Rough, Unstable, or Incorrect Idle and StallingInspect the engine mounts.
Surges/ChugglesTest the HO2S. The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The ECM reduces the amount of fuel delivered to the engine, causing a driveability condition.
Hard Start

• Temperature Versus Resistance for resistance specifications. Replace the ECT sensor if the resistance is not within specification. Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the ECT circuits for a high resistance.
• Test the idle air control (IAC) system.
• Test the fuel pump relay operation. The fuel pump should turn ON for 2 seconds when the ignition is turned ON. Refer to Fuel Pump Electrical Circuit Diagnosis.

Hesitation, Sag, Stumble

• Test the manifold absolute pressure (MAP) sensor. Refer to DTC P0106.
• Test the generator. Refer to Symptoms - Engine Electrical. Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.

Poor Fuel Economy

• Heavy loads being carried or towed.
• Acceleration rate too much or too often.
• Inspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering.

Poor Fuel Fill QualityTest for the following conditions that is applicable to the current symptom.
Difficult to fill

• Restricted vent lines
• The EVAP vent valve is stuck closed
• High fuel temperature
• A condition with the internal components of the fuel tank assembly.For more information, refer to:
• Fuel Hose/Pipes Routing Diagram
• Evaporative Emissions Hose Routing Diagram
• Evaporative Emission Control System Description

Fuel Odor

• Evaporative Emission Control System DescriptionFuel System Description.

[/COLOR]

You sir, are a life saver to the owners of newer cars. I will thank you for them.

[Paul D.]

Re: 2007 Z-06 Issues

Jimmy, when my TBSS gets a "extra lopey" idle, I run a can of SeaFoam fuel additive in a tank (or sometimes 1/2 tank) of gas and it usually clears it up. May be injector sticking. Try a can and try driving a little aggressive for a few miles. I know that will be difficult for you as I know how careful a driver you are but just force yourself. If you have the car down here in SC, give me a call. I have one of those scan tools I've never used. Most of my junk you still just tap on the side of the carb when it starts that. Not a good practice when working with electronics. Chip.