What tells EGR valve to operate?
#13
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Well the saga continues.
Today I manufactured some wires to plug into the EGR vacuum regulator solenoid valve to apply 12 volts directly from the battery and pulled a vacuum on the correct nipple on the solenoid.
With voltage applied the vacuum held. When the voltage was removed the vacuum leaked down.
This is positive evidence that the solenoid works. I could hear it clicking when the voltage was applied and removed.
Okay. This means that the 12 volts is not being removed to allow vacuum to be applied to the EGR valve.
That leads to the three sensors that tell the PCM to cycle the ground that removes the 12 volts from the solenoid and allows vacuum to go to the EGR.
Mass Airflow Sensor
Crankshaft Position Sensor
Engine Temperature Sensor
I don't think that the Crankshaft Position Sensor could be bad. I think there would be other problems.
I don't think the Engine Temperature Sensor is bad. No codes and I think there would Lean Adaptive limit codes. (I've seen this before)
The Mass Airflow Sensor could be bad or sending bad signals. You need an oscilloscope to check this one because the signal is in ascending pulses measured in cycles per second.
I could buy a $5,000 diagnostics machine or I could save my money and trade for a Chevy truck at an $8,000 discount.
Today I manufactured some wires to plug into the EGR vacuum regulator solenoid valve to apply 12 volts directly from the battery and pulled a vacuum on the correct nipple on the solenoid.
With voltage applied the vacuum held. When the voltage was removed the vacuum leaked down.
This is positive evidence that the solenoid works. I could hear it clicking when the voltage was applied and removed.
Okay. This means that the 12 volts is not being removed to allow vacuum to be applied to the EGR valve.
That leads to the three sensors that tell the PCM to cycle the ground that removes the 12 volts from the solenoid and allows vacuum to go to the EGR.
Mass Airflow Sensor
Crankshaft Position Sensor
Engine Temperature Sensor
I don't think that the Crankshaft Position Sensor could be bad. I think there would be other problems.
I don't think the Engine Temperature Sensor is bad. No codes and I think there would Lean Adaptive limit codes. (I've seen this before)
The Mass Airflow Sensor could be bad or sending bad signals. You need an oscilloscope to check this one because the signal is in ascending pulses measured in cycles per second.
I could buy a $5,000 diagnostics machine or I could save my money and trade for a Chevy truck at an $8,000 discount.
#15
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ORIGINAL: dsm1990gsx
You could always bite the bullet and take it to satan.
You could always bite the bullet and take it to satan.
Rant over.
I have yet to bring a vehicle to a mechanic much less a dealer other than warranty work and I'm not going to start now.
#18
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Measure the resistance between the terminals of the EGR solenoid. Standard value: 29 - 35 Ω [at 20°C (68°F)] 6.Replace the solenoid if resistance is out of specification
did you try this?
did you try this?
#19
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2.With the temperature sensing portion of engine coolant temperature sensor immersed in hot water, check the resistance. Standard value: 14 - 17 kΩ [at -20°C (-4°F)] 5.1 - 6.5 kΩ [at 0°C (32°F)] 2.1 - 2.7 kΩ [at 20°C (68°F)] 0.9 - 1.3 kΩ [at 40°C (104°F)] 0.48 - 0.68 kΩ [at 60°C (140°F)] 0.26 - 0.36 kΩ [at 80°C (176°F)] 3.If resistance deviates from the standard value greatly, replace the sensor.
#20
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6
EGR vacuum regulator solenoid valve
Ignition switch: "ON"
B+
Engine: idling Suddenly depress the accelerator pedal.
From B+, momentarily drops
voltages from terminal #6 of the pcm to your solenoid.
this should keep you busy for a while......lol