Mitsubishi Repair: 2001 Mitsubishi Mirage, locking gas cap, mitsubishi mirage

Question
I have a ghost in my car. On 3 instances within the timeframe of 3 months, I have pulled onto the interstate. As soon as I get up to about 60 mph, my entire car starts to shake violently. On each of those instances, I have pulled over on the side of the road, checked the tires, and checked the engine. After about 10 minutes of sitting, I start the car up and the problem doesn't come back. It happened at the beginning of a 15 hour drive to Texas and the beginning of a 13 hour drive to North Carolina. But after sitting for a while, I can continue the trip as if nothing happened. I took the car to a Mitsubishi dealership for the 100,000 mile checkup and mentioned the problem. They went over the car thoroughly (or so they said) and couldn't find a thing. I'm afraid that it's an issue that may get worse. Please help me. Thanks.

Answer
Jason: I would have the fuel pump checked, get a book so your know what kind of pressure that pump should be putting out and then check it. As it sounds like the pump is getting weak. Mitsubishi would have put your car's computer on their inshop computer. And if nothing was kicked out by the computer, then they could not see the problem. But I had a truck just a bit ago with a lot on the same problem. And it turned out to be a weak fuel pump. If with the high cost of fuel you run your car down to empty some, I am not getting on you for doing this because a lot of people do it. Hey, fuel costs a lot of money these days. Anyway the fuel is what keeps the pump cool, so if you do that to much you will cook the pump with time. Also if you don't have a locking gas cap, people will do the crazy things to cars and their tanks. I mean in the way of putting things into one's gas tank. Again not saying this happens but could have. So get that fuel pump tested as to how much pressure it should be putting out. Also change the fuel filter. As they are to be changed every 15000 miles. Most people kind of over look that part of things, if it ain't broken why fix it kind of idea. Again not saying you do this but it happens. If your car's fuel pump is putting out on the low side of the pressure, I would call that weak and replace the pump. Hope this helps and God bless: Linda