Ford: engine problems, loose wires, throttle valve

Question
lately when i start my car up, i smell gas. i took my car to an auto parts place and i got a basic computer diagnostic test done and came up as engine too rich or something like that. I also had a guy put a car starter in and we got it hooked up and pushed the button and it started but after it started, it made a screaching noise like when the car is already started and you turn the key again. my buddy suggested it was the air intake control sensor but im not for sure. another result of the diagnostic test was my transmission and the guy said it could be the trans. turnoff switch or the wires are lose because sometimes it makes a hard shift. now sometimes the car will die and it makes a purring noise like it wants to shut off. if you could help me by answering my problems then i couldnt thank you enough...thanks

Answer
hi rob,

this is a lot of questions mixed into one, so if i miss anything, i apologize.

"engine to rich" means not enough air is being mixed with the gasoline.  the air intake control sensor could be messed up.  have it checked.  if not, it may be the filters or even the throttle valve.  

also the ingniton system seems to be a little weak.  this could explain the purring noise and the random shut-offs.  the good news is that the ignition system is easy to repair and relatively cheap to fix up.  i would definitely get it straightened out.

also i do agree with the mechanic about the trans shutoff switch or loose wires.  but it is also possible that not enough trans fluid is being forced through, or it's not moving easily enough.

i hope i helped!

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