I am having a little problem with my car, I am getting a low rpm misfire like when i take off from a stop i can feel the miss. It only does it after it is warmed up, 2000 rpm+ is as crisp as it is always is. The idle of the car feels pretty much normal, any ideas on what it can be?

 

What you have sounds like the dreaded lt1 low speed stumble. I changed the Opti, plugs, wires, inlet air temp sensor, coolant temp sensor, coil, tps, manifold pressure sensor, fuel filter, gutted the cat, maybe something else I have forgotten. Check wiring, vacuum leaks and a raft of other stuff. I got a 160 degree stat and put on a manual fan switch, this way I was able to minimize the stumble. Keeping it cool minimized the effects.
I lived with it for 4 years.
One day my battery gave up the ghost, put in a new battery, no more stumble. In the process of changing all those parts I checked the voltage many times and it was fine. Just not while going down the road.
There does not seem to be a defined solution for this problem, things that work for some dont work for others.

Best of Luck.

93Z M6 RED
B&M Shifter
egr, tbb, offroad pipe

 

check the EGR valve...

 

I work at a shop, i asked one of the guys i worked with and he said egr was only at cruise not under load. The valve is original it being a 1995 i think maybe i will try it. The car has a relatively new set of plugs, wires and opti on it.

 

Check 02's and for vacuum leaks. 100's of other things. Just use the search and put in "low RPM stumble".

 

yes the egr is only SUPPOSED to work at cruise, but if its stuck open, even just a little, it will cause a miss at idle or low rpm

 

get a block off plate, or measure up one and bolt it to the back of the EGR. This will block the EGR from releasing hot air into the intake.