Hi, I've been searching all over the place for the answer to my question so I'm now asking you guys.

I recently bought an 83 Z28. It has the LG4 with the 5-speed manual. As far as I can tell everything is stock. The guy I bought it from was telling me some stuff about the electric choke which he had pulled out and was in his hands. I'm not sure if it wasn't working so he pulled it or if it was some other problem. He also pulled the ECM out and it sits in the back seat. He claimed all it was for is diagnostics. I found this hard to believe but I haven’t had any issues driving it until today.
It was getting pretty warm out here in Oregon and I was doing some city driving on my way to work and it started to run rough and sound almost like it was missing. Not sure what's happening but I was thinking maybe o2 sensor or the missing choke? I don’t really know...what do you guys think?

EDIT: Ok I made it home from work just fine. It is missing for sure, so time for a tune up. But that doesn't answer my question about the choke and ECM. =D

 

ok so I've been still searching and Clemsparks posted:

"As I research more, I'm learning more about the components of the system. So far I've got the following list:

The ECM (computer, pcm, whatever)
VSS (vehicle speed sensor)
O2 sensor (oxygen sensor)
TPS (throttle position sensor)
MCS (mixture control solenoid)
Distributor
Torque converter solenoid
EGR valve control
Air diverter valve control
SES light (service engine soon light...actually, I think it's "CHECK ENGINE" on mine)
BAP (Barometric Absolute Pressure)
MAP (manifold absolute pressure)
CTS (Coolant temp sensor)"

So now my question is how or why is my camaro running without my ecm? Or is this only for a CC quadrajet? Is mine computer controled? I have no idea. Maybe I should just plug in my ECM and see what happens.

 

I know looking at my 83 LG4, when I put the engine back together it will be getting a new vacuum advance distributor, and TCC lockup setup. My q-jet has already been swapped for a non-CCC. Check the top of the carb, is there a weatherpack connector? If not the carb is not CCC.

Next check for a vacuum advance on the distributor, if there is one, then the computer system has been taken out of the equation.

As for why the engine is missing, I will let others with more knowledge of this help you out, as there are many possibilities. I would however check the electronic spark module in the distributor, pretty common failure with the electronic module there.

Edit: contrary to what the previous owner told you, the ECM was not just for diagnostics, it controlled fuel mixture and spark curves. It was never as good as fuel injection, but it was ok at adjusting to different environments. However, I have heard nothing but bad things about the old CCC carbs.

 

Without an ECM, it'll go full rich and there's no timing control other than a tiny bit of advance built into the ignition module. It'll run and move, but performance and fuel economy will be miserable.

 

@Lectric80 I will check that in the morning!
Thank you guys I appreciate your replies.

I just got back from work and decided to do a late night test...I plugged it back in. When I started it I noticed instant difference in sound, smell, pretty much whole different characteristics. I drove it around and I seemed that its issues are gone and the power I always expected but never had became present. Check engine light is off now too...never realized how dark it was in there without it! I'm not entirely sure why he had removed it.
So just one thing now...It is still missing the electric choke. Would it be smart to purchase a new one and install it? Just a stock one or is there a better way to go?

 

A stock electric choke is fine.

 

You will want the choke working when the weather gets cold, although I don't know how cold it gets there in Oregon. The one time I was there we were using heaters in June, but that was on the coast. Just a stock replacement q-jet choke should be fine.

If you plugged the computer back in and the problems went away, I can almost guarantee you will find a CCC still in the car. Not something that you want to change, unless you are prepared for all the stuff that must be changed. You have to swap a distributor, install a lockup controller if the car is auto, plus the carb. It isn't as easy as some people think, you cannot just drop a carb in and expect everything to work correctly since the computer controls the spark curves.