Ok, to be as precise as possible, Im going to list the entire chain of events in detail, so get ready, this is a little long...
March 16th - I had my starter replaced with a remanufactured starter at a local Pep Boys after having to push-start it a few times recently. I knew it was going bad, so it wasn't a surprise.
March 16th-March 18th - Normal driving to and from work, no problems except that when I started the car in the mornings (im in the Northeast, so its cold), the RPMs would shoot up to about 2300 or so for about 3 or 4 seconds, then settle down to normal idle.
March 19th - I made a 2 hour drive to an airport, where I left the car parked for 5 days. Nothing out of the ordinary.
March 24th - I drive back from the airport, turn the car off to get my mail, and when I turn the car back on the starter motor continues to turn. I turn the car off and take out the keys, and the starter is still turning (or at least I believe it was the starter). I open the hood and realize I dont have any tools to disconnect the battery without getting shocked, and when I touch a metal part of the car, I get a small static shock. Luckily, after about 5 minutes, it stops.
March 25th - I take the car back to Pep Boys, and they replace it with another remanufactured starter and Im on my way. Heres where the problem starts.
As soon as I get the car back from Pep Boys, I start the car and the RPMs shoot up again like they did in the cold. They eventually settle down, so I start driving out. Once I do, I notice that every time I push in the clutch to change gears (manual trans), the engine will jump about 200-300 rpms while the clutch is disengaged, making it kind of odd to re-engage. This behavior occurs in all 5 gears. Also, whenever I switch into Neutral to coast to a stop, the RPMs will go to 2000 and stay there until I come to a COMPLETE stop. It doesnt matter if I slow down quickly or slowly, the engine stays at 2000RPMs until the car has COMPLETELY stopped. Once Im stopped, the engine settles around 1100-1200RPMs, typically.
I called Pep Boys and told them about this, and they said that it "sounds like a voltage problem." Im an engineer, and I realize that this is likely just blabber coming forth from the technicians mouth.
I dont know if the problem was due to the installation of the new starter, or if another part, specifically the Idle Air Control Valve (IAC), was accidentally damaged during the installation of the starter. Or it could be something else entirely, all I know is that it only appeared after the starter was installed.
Anyone have any ideas as to what this might be?