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VR V8 94 Commodore cranks but no start

Devour

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yeah its ideling ruff once the engine is warm. and i have a lack of power.. sitting in park giving it revs and its got no guts i wounder what it could be??
 

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Doesn't the engine temp change fuel mixture and turn on your fans?
EGR valve could be a issue. And if the tacho signal is missing wont that effect the IAC.
 

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Me neither I know the tps send a signal to the transmission, iac helps with idle upon load and to keep your engine around 800rpm. I doubt the rpm will do anything unless its used as a rev limiter like the new cars.
I meant pvc valve I don't think egr was fitted on the vr that I know of.
 

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TP Sensor information from the Holden Service Manual. Note the highlighted sentence.

THROTTLE POSITION (TP) SENSOR

The Throttle Position (TP) sensor is connected to the throttle shaft on the throttle body unit as shown in. It is a potentiometer with one end connected to 5 volts from the ECM/PCM and the other end to ECM/PCM earth. A third wire connects from a sliding contact in the TP sensor to the ECM/PCM allowing the ECM/PCM to measure the voltage from the TP sensor. As the throttle is moved (accelerator pedal moved), the output of the TP sensor changes. At a closed throttle position, the output of the TP sensor is below 1.25V. As the throttle valve opens, the output increases so that, at wide-open throttle, the output voltage should be about 4 volts.

By monitoring the output voltage from the TP sensor, the ECM/PCM can determine fuel delivery based on throttle valve angle (driver demand). A broken or loose TP sensor can cause intermittent bursts of fuel from the injectors, and an unstable idle, because the ECM/PCM interprets the throttle is moving.

The TP sensor is not adjustable and there is not a set value for voltage at closed throttle because the actual voltage at closed throttle can vary from vehicle to vehicle due to tolerances. The ECM/PCM has a special program built into it that can adjust for the tolerances in the TP sensor voltage reading at idle. The ECM/PCM uses the reading at idle for the zero reading (0% throttle) so no adjustment is necessary. Even if the TP sensor voltage reading were to change for some reason, the TP sensor will still be 0% because the ECM/PCM will learn the new value and it will become the new closed throttle value to be used and no driveability complaint will be present because the ECM/PCM learned a new setting.A TP sensor circuit problem will set DTC 21 or DTC 22.If the internal spring in the TP sensor fails, the TP sensor will be stuck high. A sticking TP sensor should set DTC 19.
 

Devour

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TP Sensor information from the Holden Service Manual. Note the highlighted sentence.

THROTTLE POSITION (TP) SENSOR

The Throttle Position (TP) sensor is connected to the throttle shaft on the throttle body unit as shown in. It is a potentiometer with one end connected to 5 volts from the ECM/PCM and the other end to ECM/PCM earth. A third wire connects from a sliding contact in the TP sensor to the ECM/PCM allowing the ECM/PCM to measure the voltage from the TP sensor. As the throttle is moved (accelerator pedal moved), the output of the TP sensor changes. At a closed throttle position, the output of the TP sensor is below 1.25V. As the throttle valve opens, the output increases so that, at wide-open throttle, the output voltage should be about 4 volts.

By monitoring the output voltage from the TP sensor, the ECM/PCM can determine fuel delivery based on throttle valve angle (driver demand). A broken or loose TP sensor can cause intermittent bursts of fuel from the injectors, and an unstable idle, because the ECM/PCM interprets the throttle is moving.

The TP sensor is not adjustable and there is not a set value for voltage at closed throttle because the actual voltage at closed throttle can vary from vehicle to vehicle due to tolerances. The ECM/PCM has a special program built into it that can adjust for the tolerances in the TP sensor voltage reading at idle. The ECM/PCM uses the reading at idle for the zero reading (0% throttle) so no adjustment is necessary. Even if the TP sensor voltage reading were to change for some reason, the TP sensor will still be 0% because the ECM/PCM will learn the new value and it will become the new closed throttle value to be used and no driveability complaint will be present because the ECM/PCM learned a new setting.A TP sensor circuit problem will set DTC 21 or DTC 22.If the internal spring in the TP sensor fails, the TP sensor will be stuck high. A sticking TP sensor should set DTC 19.

im only getting 12 15 and 36
 

BlackVXGTS

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Refer to the file attached:
 

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Devour

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took the map of and went to start it it was hard to start but i got it going and then it ideled ruff for a minute and then came good it just started purring, so i put it back on and now it runs welll??? weird but good for me it goes good now.. its still throwing a DTC 12 and 36 but its running really well
 

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You may have a Theft Deterrent system problem. Refer to the item below from the Holden VR Service manual. Note that the reference to High Series BCM also applies to the other series BCMs.

1.1 THEFT DETERRENT SYSTEM - GENERAL INFORMATION
Armed

Once the theft deterrent system is enabled, it can be manually armed in one of two ways:
Actively, by pressing the button on the remote coded key (DOORS button on two button remote coded key) or,
Passively, as the High Series BCM will automatically arm 30 seconds after the ignition is turned off.
When the system is armed, the start relay (located in the engine compartment relay housing) and the engine management system ECM/PCM are disabled, preventing the engine from being started.

Disarmed
With the system disarmed, the start relay and the engine management ECM/PCM are enabled, allowing the engine to be started when the ignition switch is turned to the run position.
The theft deterrent system can be disarmed by:
Pressing the doors button on the remote coded key. This unlocks the doors, turns the interior dome lamp ON and disarms the system for 30 seconds or, until the remote coded key is inserted into the ignition switch key barrel and turned to the on or run position. This causes the High Series BCM to read a security code serial data output from the remote coded key contact pin via the remote coded key reader assembly.

The system can also be disarmed by turning the ignition switch to the ON position for approximately 45 minutes.

NOTE: Should the engine not crank when the ignition switch is turned to the START position (ie due to misaligned or a faulty remote coded key reader) then pressing the button on the remote coded key (DOORS button on two button remote coded key) will also disarm the theft deterrent system.

Theft Deterrent Alert Indicator LED
The theft deterrent alert indicator LED is used to indicate the state of the system. A flashing LED indicates that the system is armed and consequently the vehicle cannot be started. When the LED is turned off, the High Series BCM is disarmed and the engine can be started.

For vehicles with Electronic Climate Control (ECC), the theft deterrent alert indicator LED is located in the instrument facia, below the centre air outlets. If the vehicle is fitted with manual type air conditioning, the theft deterrent alert indicator LED is in the dash panel centre facia escutcheon, below the radio/cassette player.

Operation
When the ignition switch is turned to the on position, the engine management ECM/PCM will request from the High Series BCM permission to start. If the High Series BCM has received the correct security code from the remote coded key, then it will respond by enabling the start relay and giving the ECM/PCM permission to start (this allows the ECM/PCM to enable fuel system control).

If the correct security code is not detected by the High Series BCM within two seconds of the ignition being turned on, the High Series BCM will then monitor for Radio Frequency (RF) signal output from the remote coded key doors button. If the High Series BCM receives the correct RF signal output from the remote coded key, it will then enable the start relay and give the engine management ECM/PCM permission to start. This feature allows engine starting should there be a malfunction with the remote coded key reader assembly.

Should the High Series BCM not receive any communication from the engine management ECM/PCM with the ignition switched on, the High Series BCM will enable the start relay after one second delay. The engine will crank, but will not start as the engine management ECM/PCM has not enabled fuel system control (no fuel is injected).

NOTE: It is very important that the remote coded key reader is aligned correctly with the ignition lock assembly, or misalignment with the remote coded key contact may occur resulting in intermittent or no engine cranking or starting.


Hi lads;
Do either of you know what's going on and how to fix the following problem?
My 2003 CV8 Monaro remote keys sometimes unlock and sometimes do not unlock the doors. Now both spare and usual keys do not start engine. The engine ignites, tries to idle then conks out. Can you help? Is this 45minute in start position all that is needed here?
 
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