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I don't have a known good EGR to test and find out if this is expected behavior. The ECU would have to continually drive the motor to hold the EGR valve position. This is difficult to test while assembled, because at least on mine, the spring pressure is adequate to push the keyed rod back down. This turns the rotor, which threads the keyed rod in and out, and would in turn depress the plunger on the EGR. Upper for open and lower for close, if I recall. The center two pins are +12VDC and the ECU, when actuating the EGR, provides ground alternately to two of the outboard pins. The keyed rod is threaded and the 'nut' it threads into is the rotor of a crude stepper motor.
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For those unfamiliar, the plunger on the valve is actuated by the funny keyed rod you can see in the photos. I remounted the valve without actuator and depressed the plunger. By the time I was done, it ran like a car with a nasty exhaust leak - just like you'd expect. I spent a far bit of time re-cleaning the intake passage from the EGR. I removed the valve entirely, and other than the sound of a horrendous exhaust leak, the car ran fine. There was no change in manifold vacuum and the car did not stumble or die as one would expect. I removed the EGR actuator from the EGR valve and manually depressed the plunger while idling. Since I still have problems I decided to look a little deeper. I had the engine out of the car over the winter and took both upper and lower manifolds off the car, soaked them in simple green, ran bottle brushes through as far as I could, installed an oil catch can - all trying to beat this problem. Fair warning, I wrote a novel for the curious. I spent some time following breadcrumbs and double checking my work this weekend. Only other symptoms that might be related is that the car stumbles between 2k and 3k on moderate throttle before fully warmed up. I don't know what the boost sensor values should be, but I don't see any red flags. The EGR solenoid appears to function normally, the EGR valve actuates, and the boost sensor output is linear (attached). I've also modified the speeds and durations with no success in bringing the system to ready. I have followed drive cycle listed here (). I don't know if this has been the case all along, or a new issue. I have finally purchased a decent OBD scanner and have learned that after about 300 miles the EGR and only the EGR is 'not ready'. I have tried cleaning the upper and lower intake manifold, cleaning the EGR, cleaning the MAF (thinking discrepancy of expected air tripping excessive/insufficient triggers could be caused by an erroneous MAF) relocating the vacuum line and cursing like a sailor. Usually, after resetting the CEL it takes 500-1000 miles to come back. She throws both P0401 and P0402 at what appears to be random.
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I have a 2000 NB, 107,000 miles which has suffered from a recurring EGR issue since I bought it 2 years and 7,000 miles ago. Hello all! First time poster, long time lurker.