I have a 93 Z28, automatic. When I give it a little gas, it sounds like it's missing or something. There's a huge loss of power. We've changed the optispark, plugs, and the ignition coil. The only thing we haven't touched yet are the wires. It just doesn't run right. I really don't know how to explain it right now. It's just a big loss of power, and it sounds like ****. Can anybody give any suggestions, anything at all to check? Thanks.

 

some things you might want to check are
1. your injectors, see if they are getting fuel or if they might be clogged up.
2. Compression test
3. adjust the rockers

Just some ideas.
I know how ya feel, I just got done rebuilding my car with the LT4 kit and i have a miss in the number 8 cylinder, and the only option left is to break down and buy a new opti.

 

Okay. It can't be any of that. We checked all the wires, and they're in the correct place, and they aren't burnt up. Could it be a bad O2 sensor or anything? It's sputtering and doesn't idle right, and has hardly any power.

 

Take it to a shop, get an estimate. Maybe they will tell you exactly what is wrong, then you can fix it yourself. I had this happen to me, but it was my opti that was causing it.

 

Sticking EGR valve, maybe?????

 

Thank you!! I'm going to check all of that today or tomorrow. I know it's not the opti, we just changed that 3 weeks ago. I'll let you guys know what it was when we get it fixed.

 

Fuel filter maybe?
Have you hooked up a scan tool to it?

 

Just for grins, and the knowledge, have you performed a compression and leakdown test?? If you rule out all other players this would probably be a necessary step in the scheme of things.

 

Are you sure?
Try to pinpoint the miss if there is one.
If you are sure it couldn't possibly be a bad injector, then run a compression test and have someone run your valves.

I still kind of think it might be a fuel problem.

 

Well, we just put a new opti in it, spark plugs, and the ignition coil. I doubt it's the fuel filter, since it's fairly new too, but I'll change it just to make sure. After that, I'll take it somewhere and get the fuel injectors checked, and a compression test. After that, I guess it couldn't hurt to change the wires too.

 

Meh...Same thing happened to me a while ago and it was my fuel pump. First off, put a pressure guage on your schrader valve. (On a 93 its near the drivers side fuel rail) Turn your key to on, but dont start it. The pressure SHOULD JUMP to 41-47 psi, and hold there. If it does, turn your key off. Then watch the pressure gauge. IF the pressure slowly drops, you could have a leaky injector, or a bad regulator. If the pressure holds, but you get under 41, its the filter or pump

 

good luck , let us know what it is.