Well, I just got my car back from a second repair shop (the first was the dealer, this latest one, an AAMCO), unfixed, because no one knows “what’s wrong with it”. Sigh.
2000 Mitsubishi Eclipse 3.0 GT. 121,000 miles. Automatic, with optional manual slapshift. I have kept up on all required service on the car. It runs GREAT, except…
After the car sits for >8 hrs, the first time I drive it, and get up to >50mph, it will “stall”. When I say stall, I mean I suddenly have no accelerator power; no RPM’s when I press the accelerator. None of the dash lights come on, indicating the engine is actually off, though. I coast over to the side of the road, moving only by momentum. I can manually downshift the car, and the RPM’s will go up accordingly, and slow me down faster. Once I get to the side of the road, sometimes before I even come to a complete stop, the car comes back “on” and I’m sitting there as if I just pulled over and off the freeway for no reason. I just get back on the road and continue on my way. It may or may not happen again during that 10 minute commute. It won?t happen again if I have driven the car within the last 8 hours or so.
This last time I had the head technician from the shop sitting in my passenger seat, computer all plugged in looking like my car got taken over by the Borg, as it happened on the freeway. His computer told him nothing. How is any of this possible? I’m starting to believe in magic 
At best I will have an ulcer shortly… at worst, well, let’s just say the freeway I use has lots of big trucks. Yikes! Please help!
Have you tried loosening up the gas cap before setting out on your commute? If the negative pressure caused by fuel consumption from the gas tank is not relieved quickly enough, gas will cease to flow and the engine will die. This is not the only possible cause, just one that is easy to test, and cheep to fix if it is the culprit.
I have not tried that, but I sure can. Thank you.