I have a 95 z28 lt1 stock everything. When I first start up the car it runs great until it warms up. When warm it looses low end power. It doesnt run bad, like it idles fine and runs ok, just seems like its loading up. I can't even get the tires to break loose when its warm. It seems to have pretty good top end, but thats it. Also it doesnt charge very good when warm. I have to bring the rpm's up while holding the brake for it to charge normally. It charges fine when cold. I just had the altenator rebuilt, and still have the same problem. I dont know if these problems are related. The oil pressure runs pretty low when its warm too. Not a problem when cold. I put a new opti and water pump on, with no change. I also unplugged my maf and ran it for a while. All I got was a check engine light. If anyone knows or has the same problem please let me know. Thanks

 

Have you tried spark plugs/wires and 02 sensors? I recently replaced all 3 and it made a big difference on how the car felt

 

Do you have anyway to run a datalog to see whats happening? You should take the car in and have the alternator tested on the car while running. You can have a bad unit that was just rebuilt. I cleaned all my connections on both the positive and negatives and you could tell it needed it. My first guess was a bad O2, but it would be nice to see if they are working correctly, instead of just replacing them.

 

I thought about a bad o2 sensor but I dont have any check engine lights on.

 

From my past experiences, you can have a bad one and not get the check engine light. Maybe someone can confirm this, since I don't know for sure.

 

When the car gets warm its like the plugs are filed or its getting flooded with gas. I also can smell gas. When I first got the car it ran great, then after I got on it pretty hard it started to give me problems the next day.

 

You should add a "signature" with all the info on the car. What's been (headers, cam, mods) done and so on. How many miles on the car? I recommend replacing the O2's when you get in the higher mileage, if they are original. 100,000+ is what some suggest and they call it a maintenance item like plug wires and other parts.