Appreciate the insight on the new valve. Did swapping it out take care of the P0488 issue for you? Also, I'm curious, how were you able to determine that the stepper motor was the problem? My OBDII setup is pretty basic and doesn't show EGR position in real-time, so I'm trying to figure out the best way to diagnose this.
EDIT #1: I came across a post suggesting that applying 12V to certain pins should actuate the valve. I'm planning to give this a try next. Here's the post for reference: Hi from Tullamarine
EDIT #2: I attempted the method from EDIT #1, and there was no movement from the valve. It's looking like the stepper motor's gear teeth might be stripped since the motor doesn't seem to engage the valve, but I hear the movement of the motor.
I definitely get what you mean about that 10mm bolt—what a pain! I was using a ratcheting combo wrench, which helped a lot, even though it was a two-click-at-a-time kind of deal. Funny thing, though—I ended up dropping one of my wrenches, and it's now a permanent fixture somewhere in the engine bay.
I spotted a Bilstein aftermarket EGR valve for about 250€. Seems like a fair price, so after EDIT #2 I decided to buy it and install it. Will be posting when the part is in place if the issue is resolved.
Thanks again for the help!
