Mitsubishi1

Hi Scotty, I'm in dire need of your expertise with my 2000 Eclipse gs 2.4L, V4! I've changed out the EGR solenoid, EGR Valve, and Cam Sensor, all within the last 2 years, but the check engine light is still on, and it didn't pass smog then, so it was passed illegally.
It's time for a smog check again, but I'm afraid it wont pass again, and refuse to throw money away illegally, and would rather repair the problem.
Now, since Memorial Day Sunday, it's been to three mechanics, which apparently are only guessing to what the problem might be. Code p0400 comes up, which is the EGR valve, but that was replaced last year. one guy said it's the EGR vacuum Solenoid, but the part he's asking for, is clearly for a V6, not a V4. Supposedly the vacuum lines are clear, and there are no apparent electrical shorts anywhere, as stated by the auto electrician, which did inform me of a leak in the exhaust manifold. Lastly, I drove it on the freeway, was exiting on the off ramp, and it jerked and shut off. I had to keep turning it on, gun it a few feet, and turn it back on st least fifteen times until I was able to clear it off the road safely.
I need to get this issue resolved asap! Can it be a faulty EGR valve, or perhaps it was installed incorrectly, hence the continued p0400 code? or can it be something completely different?
Thank you Sir, I'd greatly appreciate any advice and guidance you offer.
Ana-Lilia