95 z28 that has a low end miss
#1
95 z28 that has a low end miss
Hey guys I'm new to the forum and have done a lot of searching but haven't quite for exactly what I'm looking for. I just bought a 95 z28 auto, motor rebuilt about 30k ago with new plugs and wires at that time, opti is 2 yrs old, new tps, original coil (161k). It idles slightly rough and rich, it kinda chugs when you get on the gas below 2k rpms, above 2500 it starts to run great and pull hard. Crusin at 55mph it bucks real bad until i get the rpms up above 2500. I bought this as a spare summer toy and don't want to just start throwing parts at it cuz money is tight. I really want to get it right the first time. oh also the cats are hollowed but have been for 40k. Thanks and look forward to hearing back!
#3
^^^ agree best to have it sanned for trouble codes. the car being a 95 u may have problems finding a place with the correct scanner so do some calling around to the local parts stores to see if they can scann a 95 for codes. autozone will sometimes have the right one.
#4
I actually work at a VW dealer so I have access to some stuff like a snap on mt2500 scanner. A long time gm service advisor said it's the fuel pressure regulator. When I pulled the vac there was no visible fuel but it did smell like it. I guess it's a good expanation to it stumbling at low rpm and running rich. Not sure what else would cause a rich condition as such. Thanks guys
#5
well if your running rich they may cause it to seem like a miss, but its either bogging which all that extra fuel will cause it to have that rough idle, there are thousands of reasons that it would run rich, do you have anything done to the car as far as headers or cats gutted or cut out? also check your spark plugs
#8
Lets see? Hollowed out cats? Mmmmmm, you don't by any chance have headers do you? I would opt for stock high impedence plug wires and stock plugs. A basic tune up. If you look under the hood at night you my identify some wires arching. I purchased some stock LT4 spark plug wires. Why? Well they are matched to the ignition system. Well, not excactly. Two of the wires had straight boots and the coil wire was different, but I have a set of stock slightly used wires which I swaped boots with and ofcourse used a stock coil wire for my year car! The ignition system picks up noise interference which is generated by all the power being made? Keeping it short, I would do a basic tune up and your miss will probably disappear and it's a good start to trouble shoot.