is my EGR valve bad
 

well my car has been acting up alot like when its cold it runs great but as soon as it starts to warm up it starts to bog down and i give it gas and it just dont want to do anything till it down shifts into 3rd and my rpms went from 2200 at 55MPH to 1900 at 55MPH ..i was at captain Ds drive thru waiting about 20 min to get my food at 800 RPMS and all of a sudden my car mufflers got loud like they use to be and the car started to run great again at 1000 RPMs and it had the TORQUE IT USE TO HAVE untill i started to pull closer to the window then it droped rpms again but now i barlley have TORQUE maybe i need to clean the intake what do you guys think i got some carb cleaner can i use that to clean the intake thanks

You did not mention what year and engine, but being you posted in the LT1 section I guess you have an LT1 engine. From what you describe, a tune up (plugs, wires, filters) is a good idea, but there is a good possibility that the Opty is on its way out.

its been doing this for about 7 months sometimes i got power and other times i dont plugs wires been done new filter new o2 sensors new MAF sensor that made the shuttering go away lol..um have not changed the opti yet cause the guy i bought it from showed me reciepts of every thing he did to the car and it was a complete OVERHAUL pushing 589HP
with only about 57,000 on her new motor ... i can gun her at times at a stop light and it will burn rubber but other times it will chirp the tires a bit and slowly gain speed like a stock v6 will keep up till i hit 3rd gear then im gone :( but it use to be like chuuuuurpppp gone in 1st lol

hope this helps maybe slow throttle response sometimes idk

ohh it is a 94 z28 lt1 camaro :)

ohhh idk if this will help but since this has happened my brake pedal has been easly pushed in like at start up i can tap the brakes and it will slide but now i have to push them in really hard to slow down but at times there stiff again and i only have to slightly push them

check fuel pressure and flow?

could be the anti lock brake brain. check for a vacumn leak, attention to the power brake power assist vacumn hose; oh yah check brake fluid level.:)

ohh just found out that it might be my IAC bad idle air control since i replaced everything else and checked fuel pressure all is good cept i didnt change IAC where is that located on a 94 z28 camaro below the TPS

yes it is

how do i check the flow ?? like you said ive checked the pressure which was good

edit= hey how come when my torque converter locks up and i press the brake pedal slightly to unlock it it starts to run perfectly but once i let off the brake pedal it starts to mess up again you think my brake switch is messed up lol just a wild guess :)

ohh and another thing if i sit at a light for too long my SES light will come on and it will really run bad like try to shut off and crap when i let off the gas at low speeds less then 40 MPH

just hook a hose up to the fuel line and put the hose in a container. turn the key on and see if u get good flow. if almost nothing is coming out u know there is a blockage or the pump is having problems or something in the tank. when the converter unlocks the motor has no load on it. does not need as much gas or spark to run that would point to limited fuel or spark. have it scanned for trouble codes. hopefully it has something stored to tell us.