I just bought a 1999 Z28 Camaro about 6 months ago, it just recently started missing. The problem is when i start off taking off slow it feels like its holding itself back and then it will suddenly just grab and go. Kinda like a catch up thing. The car has a Gigalotta air lid, SLP Long Tube Headers, SLP Exhaust with no cats, slp ultra z hood that is functional. When the "Z" is running good it hauls *** i havent tooken it to the drag strip yet till i figure out what these problems are. I have taken my car to a GM Dealership that a buddy works at and this guy he kno owed him a favor for doing some body work to car of his, they ran the computer on it and all my 02 censors are showing up, multi cylinder misfire is showing, and 2 fuel air codes. My left bank 2,4,6,8 is the misfire however he said my Coil Packs are fine, and so are my plugs and wires my car dosent always misfire just sometimes. My fuel pressure was good but when they read all this it wasnt acting up at the time. My fuel pump is humming, this has happend be4 but quit and just started a couple of days ago again and since this has started it will not let me rev it high so i guess its running extremely lean. I am a body man not a a mechanic by any means. The people at the dealership told me i need to get some 02 sensor simualtors, the only place i can find them is speedinc.com but however ive read plenty of things on this website and it looks like i need to say screw that and get a diablo programmer to delete the 02 codes. And now about the fuel pump it started humming about 3 months ago and doin the reving thing and then it stopped, i ordered a fuel pump but since it stopped i sent it back like a week ago and now its doing it again. i bought a Venom Racing fuel pump from Summit Racing. Any ideas on a fuel pump? was that a good choice? I just recently caught a Nitrous System on a deal, its wet, and 150 shot, what should i take in account after i fix the above problems? Sorry this is so long but im a bodyman not a mechanic.lol. I am currently painting my Z tho and i will have some pics of it up soon.

 

you know...it may be your fuel filter. you didnt mention the last time you changed it but if its been a while a clogged fuel filter will cause every single one of those symptoms.

- it cause lots of back pressure which will overwork the pump (making it "hum")
- it will cause fuel pressure drop off at higher rpms, fuel pressure fluctuation, and the wierd "catch" feeling when accelerating slowly from a stop.
- the resulting lean condition and pcm trying to compensate could easily cause a misfire and fool with your o2's

...

if you have changed you fuel filter recently then i don't have the slightest idea what the problem is, but i would recommend walbro fuel pumps, they're pretty solid.

 

ive change the fuel filter here recently, where can i find one of those fuel pumps at? and will it be good enough if i add bigger injectors? i have a nitrous kit that i plan on adding down the road....will it be good enough? my car has one of those plugs in my EGR that wouldnt cause any of this would it....ive researched this to see if it would and it dont seem like it would.

 

http://www.speedinc.com/catagory.cfm...%20/%20Cooling
GSS341-LS1 Intake 255L Walbro Fuel Pump - LS1 (1999+) Direct Fit Kit $139.99