It seemed I was having trouble with my plugs, with miss fire,
and not able to pick up speed without losing power and not
able to accelerate. So I was going to change them out, being
the wiz kid I am, I thought I was taking out the plugs, only to
realize I was disconnecting the fuel injectors. ( Not to Bright )

Once I figured out there was no plugs there, and having trouble
getting them back together, I called it a day. The next day, on
the side that was giving me the most trouble, I took the injectors
all the way out, cleaned them up a bit, and reassembled them
to a tight seal.

Thinking to myself, ( what a dumuss ) I went ahead and started
it up. No problem, except it won't exceed 3 RPM"s. I just knew I
really made a bad mistake. I turned it off, and gave up. About an
hour later I went out to try again, same results, except this time
I punched it like I was going to pass someone. It worked, I took it
for a ride, everything seemed ok, I punch and it fly's like a rocket.

Don't know what I did, but it runs better that its ran sense I owned it.
This was 4 days ago, every other time I start it up I can't get
past 3 RPM"s, then the next day, no problem. My question is what
the heck is going on? I have a few guesses, but I would like to hear
from y'all, thanks ahead for your time, and I hope my guesses match
what you guys say,

 

The 3k limit is enforced by the ECM due to sufficient codes invoke a 'restricted performance' status. Your MIL/CEL should be on. Read the codes or have them read and report the actual number codes back (P0xxx) not the English translation probably produced incorrectly by the auto parts store master technician.

 

Also note that you can't go over 3000 in neutral or park.

 

Before when I tried it would seem like it wasn't getting any gas,
but it will get up to 5K, in park, but I will not do that any more.
I'll drive it and see if it will get above 3, if not then there is a
problem somewhere.

 

+1. My XKR is that way too.

My A8L will rev freely in Neutral or Park and is one of the nicest sounding V8s I've ever heard (helps I got rid of the mufflers). But I don't like just revving unloaded engines high.