Any suggestions as to why my engines RPM goes to almost 2500 at startup? It seems too high?

A vacuum leak can cause a higher than expected run speed while out of gear, so it's possible there's a vacuum leak somewhere causing the higher than expected run speed at start up. Then again, it's also entirely possible that the engine is just designed/programmed from the factory to briefly run near 2500 rpm upon cold starting to light off the catalytic converter(s) faster or for any number of other reasons. If it's always run to 2500 rpm at cold start since you've had it, it might not actually be a "problem" at all. My wife has a car (a 2013 Hyundai Elantra) that also revs to above 2000 rpm when you first start it cold. It doesn't do it when you start it warm either and it's run like that since the day we bought it brand new.

One way to determine if this is normal operation for your car or not would be to find another car like yours, same age, model, engine and transmission type and see/ask if that person's car behaves the same way at cold start versus warm. If it does, it's most likely just doing it by design and there's no problem to worry about.

The computer is doing it. It's the cold start routine. Its your air idle motor or air idle valve doing this.

My Ford Ranger does this, and it is so irritating, because my oil filter sticks out of the engine sideways, and overnight there is enough time for the filter to drain through the oil pump back into the oil pan.

So when I start it in the morning, there is NO oil pressure for several seconds, and in the cold weather the crankshaft bearings were rattling! Mine goes instantly to 2500 rpm and then slowly idles down.

So I unplugged the air idle valve and made an electronic pulse width modulator and I have a variable control on my dash to turn the idle down at start, and idles really slow for several seconds, until I get oil pressure, then I turn the idle up.

I started making a right angle oil filter adapter so the filter points down, so it can't drain while the engine is off, but I haven't finished it yet. I got this pickup used and it did it right away, so I changed things.

If it's a modern car, the computer controls the idle speed.....many factors unknown to us (miles, maintenance etc) could affect how much it pollutes on start-up but the normal response is to increase engine speed to burn more pollutants. Of course, there could be a problem with a sensor or the ecm itself . . . no way of knowing what your efforts with the throttle cables has done.

added @ Dominic: but apparently I know more than you . . . . so why don't you go back there and start turning screws and loosening things and see if that makes it better. Twit.

Upon the return of colder weather the computer will quite possibly sense the lower temperature and do that. You may not have any control over that and your assumption that it is too high may not be valid.