bspecmr2

The problem was fixed 2 months ago. It was a faulty VSV (one of the few in the EGR system).
However I have a new check engine light code, which popped up last week and will get this diagnosed next week. I'll post an update.

TLDriver

iTrader: (4)

I had the same issue, I looked at my vacuum lines and one had a small crack, VSV was not within the OHM range suggested, the gas cap was not working well, cleaned out the EGR valve and my canister (passenger side by firewall) had a small clog. I noticed the code popping up usually when I would have 1/4-1/2 tank of gas but not at full. No codes showing from last time I ran my car.

Chanh

Have you tried to replace or clean O2 sensor? I cleaned O2 sensor with WD40 then gasoline then blow dry the code went away for a month.
I got the engine light back on. I checked the EGR VSV (vacuum control solenoid). When measured resistance across the 2 terminal of the EGR VSV saw it was several K Ohms, should be around 26 Ohms. I went to junk yard and pulled 3 of them, paid for it. I put it on and problem gone. I noticed before I fixed the problem the idle speed was around ~1200 RPM and after I fixed the problem the idle speed dropped to ~800.