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HELP! Newbie Ignition problem

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Old Aug 9, 2004 | 10:45 PM
  #1  
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Default HELP! Newbie Ignition problem

On the way back from the lake in a used FRC with 69k miles I stopped to get as soda.

When I started the Vette it died and the only way to keep it going weas to hit the gas.

SYMPTOMS:

1) extremely rough idle that can only be solved by 2K RPM. Like one cylander is DOA.

2) All ignition wires re-seated.

Anyone who isn't a newb moron car geek got any input.. I need help!
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Old Aug 9, 2004 | 10:51 PM
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Did you notice any codes ?
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Old Aug 9, 2004 | 11:17 PM
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Code I havent looked up yet.

I don't care for codes though they work. I'd rather hear C5 selutions
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Old Aug 10, 2004 | 12:31 AM
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Originally Posted by Raedon
On the way back from the lake in a used FRC with 69k miles I stopped to get as soda.

When I started the Vette it died and the only way to keep it going weas to hit the gas.

SYMPTOMS:

1) extremely rough idle that can only be solved by 2K RPM. Like one cylander is DOA.

2) All ignition wires re-seated.

Anyone who isn't a newb moron car geek got any input.. I need help!

Pull the codes. Anything else is just a shot in the dark.


http://www.stengel.net/diccodes.htm
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Old Aug 10, 2004 | 07:46 AM
  #5  
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You need to know what is broken before you fix it, that is what the codes tell you, if you want to ignore the codes, then just do what the dealer apes do, replace everything.
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Old Aug 10, 2004 | 07:55 AM
  #6  
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Thanks! Good site

I guess you can't drive 120MPH+ forever and not hurt something... or go to jail

lol I'm such a newb. I didn't even know you could pull codes without a computer. I wish my Jimmy 4x4 had codes (that I could pull up without a notebook and software anyway)

I've only had the car for a few weeks so make fun of me if you like


codes:

(check engine light on)

P0300 Engine Misfire Detected
P0352 Ignition Control #2 Circuit
P0355 Ignition Control #5 Circuit
P0506 Idle Speed Low
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Old Aug 10, 2004 | 09:04 AM
  #7  
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Richin Chicago
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From: Wilmington NC
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Originally Posted by Raedon
Thanks! Good site

I guess you can't drive 120MPH+ forever and not hurt something... or go to jail

lol I'm such a newb. I didn't even know you could pull codes without a computer. I wish my Jimmy 4x4 had codes (that I could pull up without a notebook and software anyway)

I've only had the car for a few weeks so make fun of me if you like


codes:

(check engine light on)

P0300 Engine Misfire Detected
P0352 Ignition Control #2 Circuit
P0355 Ignition Control #5 Circuit
P0506 Idle Speed Low
P0300:

CIRCUIT DESCRIPTION
The Crankshaft Position Sensor (CKP) is mounted through the side of the engine block at the rear of Bank 2 behind the starter assembly. The CKP sensor works in conjunction with a 24X reluctor wheel on the crankshaft. The reluctor wheel is inside the engine immediately in front of the rear main bearing. The PCM provides a 12 volt power supply to the CKP sensor as well as a ground and a signal circuit.

A misfire causes a change in crankshaft speed. The PCM times the interval between each pulse and compares each new time interval with the previous one in order to determine when an excessive change in crankshaft speed has occurred. You can expect a certain amount of acceleration/deceleration between each firing stroke, but if the crankshaft speed changes are greater than an expected amount, the PCM interprets this as a misfire.

The PCM uses the CKP sensor for both spark and fueling. As the crankshaft rotates, the reluctor wheel teeth interrupt a magnetic field produced by a magnet within the sensor. The sensors internal circuitry detects this and produces a signal which the PCM reads. The PCM uses this 24X signal in combination with the camshaft position sensor lx signal in order to accurately determine crankshaft position. The PCM also calculates a 4X signal from this information. The PCM uses the 4X signal for internal calculations. The 4X signal also provides a tach signal for any device which requires one.

Observe that as long as the PCM receives the CKP sensor 24X signal, the engine will start. The PCM can determine top dead center for all cylinders by using the CKP sensor 24X signal alone. The Camshaft Position (CMP) sensor lx signal is used by the PCM to determine if the cylinder at top dead center is on the firing stroke, or the exhaust stroke. The system attempts synchronization and looks for an increase in engine speed indicating the engine started. If the PCM does not detect an increase in engine speed, the PCM assumes it incorrectly synchronized to the exhaust stroke and re-syncs to the opposite cam position. A slightly longer cranking time may be a symptom of this condition.

CONDITIONS FOR RUNNING THE DTC


DTCs P0101, P0102, P0103, P0117, P0118, P0125, P0335, P0336, P0341, P0342, P0343, P0500, P0502, P0503, P1120, P1220, P1221, P1258 did not set.
The engine speed is between 425 RPM and 3000 RPM .
The ignition voltage is between 10 volts and 18 volts .
The engine coolant temperature is between -7°C (19°F) and 130°C (266°F) .
The fuel level is greater than 10 percent.
The throttle angle is steady within 1 percent.
The ABS and the traction control are not active.
The transmission is not changing gears.
The AIR diagnostic test is not in progress.
The A/C clutch is in a steady state.
The engine is not in fuel shut-off or decel fuel cut-off.
The ABS signals are not exceeding rough road thresholds.
CONDITIONS FOR SETTING THE DTC


The PCM determines that an emission type Misfire is present.
The PCM determines that a catalyst damaging Misfire is present.
ACTION TAKEN WHEN THE DTC SETS
The PCM will illuminate the Malfunction Indicator Lamp (MIL) under the following conditions:


The PCM illuminate the Malfunction Indicator Lamp (MIL) on the second consecutive drive trip that the diagnostic runs and fails, if the diagnostic fails under the same conditions (load, RPM, temperature, etc.) as the previous ignition cycle that the test ran and failed.
The first time the diagnostic fails, the PCM records the operating conditions in Failure Records.
The second consecutive drive trip that this diagnostic fails [under the same conditions (load, RPM, temperature, etc.) as the previous ignition cycle that the test ran and failed], the PCM stores this information in Freeze Frame. The PCM copies any data previously stored in Freeze Frame and copies the data into the Failure Records. The PCM then overwrites the Freeze Frame. The only exception to this is if a Misfire DTC was already recorded in Freeze Frame. In this case, the Misfire data stays in Freeze Frame and the PCM updates the Fuel Trim data in the Failure Records.
The PCM determines the percent of misfire over a 1000 revolution period is high enough to cause excessive tail pipe emissions. The PCM illuminates the Malfunction Indicator lamp the next consecutive ignition cycle that the diagnostic runs and fails, if the diagnostic fails under the same conditions (load, RPM, temperature, etc.) as the previous ignition cycle that the test ran and failed.
The PCM determines the percent of misfire is high enough to cause Catalytic Converter damage. The PCM flashes the Malfunction Indicator lamp when the diagnostic runs and fails.
CONDITIONS FOR CLEARING THE MIL/DTC
The PCM turns the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail within the same conditions that the DTC last failed.

IMPORTANT: If the last failure was during a non-typical driving condition, the MIL may remain ON longer than the three ignition cycles. Review the Freeze Frame/Failure Records for the last failure conditions.



A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
A last test failed (Current DTC) clears when the diagnostic runs and does not fail.
Use a scan tool in order to clear the MIL/DTC.
DIAGNOSTIC AIDS

IMPORTANT:


Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Diagrams.
Running the vehicle out of fuel causes sufficient misfire to set DTC P0300. A vehicle that is out of fuel may have DTCs P0461/P1431 also set.
A restricted fuel filter can cause sufficient misfire to set DTC P0300. Refer to Fuel System Diagnosis. See: Diagnostic Information and Procedures\System Diagnostic Tables\Fuel System Diagnosis
A misfire that only occurs during certain conditions may be difficult to locate. Observe freeze frame and/or failure records to determine when the DTC set.
Excessive vibration from sources other than the engine could cause a misfire DTC. The following are possible sources of vibration:
Variable thickness brake rotor
Propeller shaft not balanced
Certain rough road conditions
Observe, if more than one cylinder is mis-firing, the scan tool may only display one cylinder mis-firing. This is not apparent until the repair is completed. Also, if an ignition coil/module ground circuit is open for one side of the engine, the scan tool may only display 2 or 3 cylinders mis-firing. Inspect the ground circuit for the ignition coil/modules on the cylinder bank of the engine that has more than one cylinder mis-firing.
A misfire may not be apparent at idle. The misfire may only occur above idle under a load. Road test the vehicle and monitor the misfire current counters.
For an intermittent condition, refer to Symptoms. See: Diagnostic Information and Procedures\Symptoms
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.


The Misfire Current Counters will not increment if certain DTCs set at the same time or after DTC P0300 sets. Refer to Conditions for running DTC P0300 for applicable DTC list. If more than one cylinder is misfiring, the Misfire Current Counters may increment for only one cylinder. Example: Cylinders 1 and 8 are both misfiring, yet only cylinder 8 increments on the Misfire Current Counter. If one of the injector fuses is open, only two or three Misfire Current Counters may increment for the corresponding side of the engine. Wetting down the secondary ignition system with water from a spray bottle may help locate damaged or deteriorated components. Look/listen for arcing or misfiring as you apply the water. If the Misfire Current Counters are incrementing and there is no apparent misfire, an erratic CKP sensor signal could be the cause. Perform the diagnostic table for DTC P0335 first if this condition is suspected. If a misfire is present and you suspect a fuel control concern, force the fuel system into Open Loop using the scan tool and allow the engine to run for a few minutes. If this eliminates the misfire, refer to any fuel control related DTCs which are set. If no other DTCs are set, refer to the Engine Scan Tool Data List. See: Diagnostic Information and Procedures\Vehicle On-Board Diagnostics (Accessing and Clearing Codes)\Scan Tool Diagnostics\Scan Tool Data List
The cylinder with the more significant misfire may cause another cylinders counter to increment only by a small amount.
If the engine misfire moves with the spark plug, this is good indication that you should replace the spark plug.
If you cannot find any fuel system conditions, go to Engine. An engine mechanical condition can cause a spark plug to gas foul. Inspect for loose rockers, collapsed lifters or worn camshaft lobes. Refer to appropriate procedures in Engine.
If the customers concern is the MIL is flashing, this indicates that a Catalyst Misfire has occurred. Drive the vehicle in the conditions to run the catalyst diagnostic. Refer to DTC P0420 Catalyst System Low Efficiency Bank 1 and/or DTC P0430 Catalyst System Low Efficiency Bank 2. See: P0420 See: P0430

P0352:

CIRCUIT DESCRIPTION
The ignition system on this engine uses an individual ignition coil/module for each cylinder. The PCM controls the ignition system operation. The PCM controls each coil using one of 8 Ignition Control (IC) circuits. The PCM commands the IC circuit low when a spark event is requested. This causes the IC module to energize the ignition coil to create a spark at the spark plug. Each ignition coil/module has the following circuits:


A power feed
A ground circuit
An IC circuit
A reference low circuit
Sequencing and timing are PCM controlled. This DTC sets when the IC circuit is out of range.

CONDITIONS FOR RUNNING THE DTC
The engine is operating.

CONDITIONS FOR SETTING THE DTC


The PCM detects the ignition control (IC) circuit is grounded, open or shorted to a voltage.
Conditions met for less than 1.0 second .
ACTION TAKEN WHEN THE DTC SETS


The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC


The PCM turns the malfunction indicator lamp (MIL) OFF after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed (current DTC) clears when the diagnostic runs and does not fail.
A History DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
Use a scan tool in order to clear the MIL/DTC.
DIAGNOSTIC AIDS

IMPORTANT:


Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Diagrams. For an intermittent, refer to Symptoms. See: Diagnostic Information and Procedures\Symptoms
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.


This step verifies that the fault is present.
This step verifies the integrity of the IC circuit and the PCM output.
This step tests for a short to ground on the ignition control circuit.

P0355:

CIRCUIT DESCRIPTION
The ignition system on this engine uses an individual ignition coil/module for each cylinder. The PCM controls the ignition system operation. The PCM controls each coil using one of 8 Ignition Control (IC) circuits. The PCM commands the IC circuit low when a spark event is requested. This causes the IC module to energize the ignition coil to create a spark at the spark plug. Each ignition coil/module has the following circuits:


A power feed
A ground circuit
An IC circuit
A reference low circuit
Sequencing and timing are PCM controlled. This DTC sets when the IC circuit is out of range.

CONDITIONS FOR RUNNING THE DTC
The engine is operating.

CONDITIONS FOR SETTING THE DTC


The PCM detects the ignition control circuit is grounded, open or shorted to a voltage.
Conditions met for less than 1.0 second .
ACTION TAKEN WHEN THE DTC SETS


The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC


The PCM turns the malfunction indicator lamp (MIL) OFF after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed (current DTC) clears when the diagnostic runs and does not fail.
A History DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
Use a scan tool in order to clear the MIL/DTC.
DIAGNOSTIC AIDS

IMPORTANT:


Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Diagrams. For an intermittent condition, refer to Symptoms. See: Diagnostic Information and Procedures\Symptoms
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.


This step verifies that the fault is present.
This step verifies the integrity of the IC circuit and the PCM output.
This step tests for a short to ground on the ignition control circuit.


P0506:


CIRCUIT DESCRIPTION
The throttle actuator motor is a TAC controlled DC motor located on the throttle body. The motor drives the throttle plate. In order to decrease idle speed, the TAC commands the throttle closed reducing air flow into the engine and the idle speed decreases. In order to increase idle speed, the TAC commands the throttle plate open allowing more air to bypass the throttle plate. If the Actual idle RPM does not match the Desired idle RPM within a calibrated time, this DTC sets.

CONDITIONS FOR RUNNING THE DTC


DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0171, P0172, P0174, P0175, P0200, P0300, P0440, P0442, P0443, P0500-P0503, P1120, P1220, P1221, P1441 are not set.
The engine is operating for at least 60 seconds .
The ECT is greater than 60°C (140°F) .
The IAT is greater than -10°C (14°F) .
The BARO is greater than 65 kPa (9.4 psi)
The system voltage is between 9 volts and 18 volts .
Vehicle speed is less than or equal to 1.6 km/h (1 mph) .
APP Indicated Angle is 0 percent.
CONDITIONS FOR SETTING THE DTC


The Actual idle speed is 100 RPM lower than the Desired idle speed.
All of the above conditions present for 5 seconds .
ACTION TAKEN WHEN THE DTC SETS


The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC


The PCM turns the malfunction indicator lamp (MIL) OFF after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test tailed (current DTC) clears when the diagnostic runs and does not fail.
A History DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
Use a scan tool in order to clear the MIL/DTC.
DIAGNOSTIC AIDS

IMPORTANT:


Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Diagrams. For an intermittent, refer to Symptoms. See: Diagnostic Information and Procedures\Symptoms
TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.


This test determines whether or not the engine can achieve the commanded RPM, and if not, whether the RPM is too high or too low.
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