RE: What tells EGR valve to operate?
 

remove the whole plate first #12421a

RE: What tells EGR valve to operate?
 

Tried that. Can't get a wrench on 3 of the bolts much less a socket.

RE: What tells EGR valve to operate?
 

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.

RE: What tells EGR valve to operate?
 

You could always bite the bullet and take it to satan.

RE: What tells EGR valve to operate?
 

No. I've been meaning to learn this crap for years now and I figure I may as well startnow. Stupid democrats and EPA. Billions of cows put out millions of tons more emissions than a 1965 Chevy with a carburator and points. Simple. Fuel, fire, compressionand timing.
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.

RE: What tells EGR valve to operate?
 

Is your check engine light coming on, are you getting p0401?

RE: What tells EGR valve to operate?
 

Yep. P401 and after I work on it P403 because I will start it with something unplugged. Once cleared, the P401 comes back.

RE: What tells EGR valve to operate?
 

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?

RE: What tells EGR valve to operate?
 

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.

RE: What tells EGR valve to operate?
 

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