Engine Mechanical problem
1995 Ford Aerostar
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When we are going to start our van it takes about three trys to finally start. We then will be driving and then it will begin to chug like it wants to die, then we have to floor the gas for it to stay going or it will just die if we slow down and the check engine will come on. We have to pull over wait a few minutes and then start the van in a few trys it will go. So, what is the problem? We where told it was the oxygen sensor, what is that and where would it be to change it?