james96z28

I know there was another thread with this same title, but I didn't want to piggyback on someone else's thread.
My 96 Z28 is running, driving and idling very rough. The car was fine one day and the next day it was running rough. I found the other thread with this same title and from that thread I replaced the ignition coil and ignition control module. No good, same issue, it almost seems worse.
I'm thinking it's the opti now, but would like to get help here if at all possible.

Should I be seeing any codes with a bad opti or could this be anything else?

Also, the car has been a little hard to start for some time.

Thanks for any assistance anyone can give.

James

bungy74

opti will do that, but then again so would water in your fuel.

bungy74

i also would do a fuel pressure test

djjab57

iTrader: (17)

And look for a burnt wire

Zlow28

iTrader: (11)

Does the idle surge? or does it just stay high?

Lately ive been seeing a lot of threads where people get bad fuel. Any out of the ordinary sounds like whisteling or vibrations?

SteveWs6

iTrader: (1)

Don't overthink it either. If the car hasn't been tuned up in a while, give it some plugs and possibly wires. Use Seafoam on it. And one thing that's been very successful for many people on here is cleaning the Mass Airflow sensor. You can either use a cotton swab with rubbing alcohol and very gently clean the wires in it, or purchase CRC MAF cleaner from Advance or another store. Start with the simple stuff especially because the Opti is such a pain to change

james96z28

Everything you suggested here I have already done, from a tune up, using Seafoam in the gas tank, cleaning the MAF gently with cotton swabs and alcohol. I have also replaced the O2 sensors, the ICM and the ignition coil. One thing my scanning software shows the Air pump to be disable, but all air lines and pipes to the headers, etc are hooked up.

Also the idle surges like it has a huge cam in it and the car vibrates and shakes from the rough idling and running.

The day before the problem started happening I drove the car some parked it in the garage and smelled a rotten egg smell like a new catalytic converter smell. Could it be the cat converter?

Ed Wright

iTrader: (1)

Someone that has a Tech2 and knows how to use it should be able to diagnose it for you. Nice thing about OBD2, makes diagnostics easier. If you have a weak cylinder, it will even tell you which one. Could have paid to have it correctly diagnosed for less that you spent on un-needed parts. Sometimes it's wise to hire a pro.

BigD383lt1

Have you checked out out your vacuum system... I have found that leaks will truly screw the pooch in these cars! When my car was tuned at the advice of my tuner I capped off all of the vacuum system. He gave me a bunch of rubber caps well the car ran good for a short time but then after a couple of months the rubber started to deteriorate from all the heat and then all of a sudden the car was running rough Idling like crap and I found myself having a hard time with a/c and breaks. I upgraded my vacuum system to the 96-97 cars and after that the car has ran like a dream.

james96z28

Amen to that brother Ed! That is why I have it in a very reputable, honest shop right now!

james96z28

You almost had it..... it is the #6 plug wired that was rubbing on something and rubbed halfway through the wire. The shop wants to do all plug wires for $900 but I just called them back and said I just want #6 wire replaced because the plug wires were replaced back in June. Waiting on a callback and a yes or no and if yes, a price.

james96z28

Nice Camaro, looks kind of like mine. It's a 94, correct? Do you have t-tops?

sscamino

Holy crap 900 bucks??? Is that with a new opti?? I know rates are different per different locations, but around here you can get new plugs and wires in a lt1 car for around 260.00 bucks..

djjab57

iTrader: (17)

There going off the price of hours the book calls for.

Ed Wright

iTrader: (1)

I would be talking to whoever you had put the new wires on in June. If they had done their job correctly this would never have happened. Maybe they will take care of it.

bungy74

a good way to check for spark arc is to open the hood and look in there with the motor running in the dark. I just found bad wires on my camaro recently that way.