'93 Ford Explorer issues - help please

hi. We have a '93 Ford Explorer that has about 150k miles on it and we recently had several repairs done to it. The starter and solenoid were changed out; the air flow sensor went out two months ago; and the exhaust pipe and muffler as well and we recently started to have a problem with the car starting w/o us having to apply the gas pedal. Does it sound like the fuel injector or fuel pump (I am not sure of which one is on the car) is having problems giving gas?

Not to mention, we are also burning more gas as well. There doesn't seem to be any smoke blowing out of the tailpipe but it is going very fast during the day. This is a bad thing because we've just popped a bunch of money into some of these other repairs and we're hoping to ride this car 1100 miles to return to our home real soon.

Please advise.