Hi,I had an alternator problem before.And i've changed my alternator one week ago.And everything was working fine.But there's a orange cable coming out from the positive pole of the battery and it was disconnected when i first bought the car.And it's still disconnected.It has a plastic connection part just like the fuse at the back of car stereos.But little bit smaller.It's orange.Everytime i connect this my rpm goes up around 2000.And check the engine light goes away.If i disconnect it check the engine light comes up and car is working fine.Today i've connected that again to see if there'll be a diffrence after changing the alternator.But it did the same thing.Then i disconnected again.At night i was gonna go somewhere and started the car.Now the alternator is not charging again.I have 1 year warranty on my alternator so it's not a big deal.But that wire i coudn't figure it out what it's for.And i don't know if it has any connection with my alternator.It's impossible to see where the wire is going.Cuz it's covered with plastic with bunch of other wires.It goes into that plastic near spark plugs.Does anyone have any idea what this cable is for?This is the third time i'm trying to find an answer.Any help wil be appreciated.

 

What is the Check Engine Light for? Did you ever pull the code?

 

Yea i've tried once but nothing happened.Somebody in this forums told me that 84 models doesn't have computers.But i'm not sure if mine has one or not.

 

Well I think that wire actully provides power to the computer... is it on a 84?? Thats probally why when you hook it up and diconnect it your car is surging cause the comp controlls the carb,... I many be wrong but if it is the wire im thinking then i think im right... I would leave it hooked up after you get your alt problem fixed and drive your car for alittle while and then see how it idles... Kevin

 

Holy crap!

That "single" orange wire is the power feed for the ECM. I disconnect it all the time to clear codes. The reason you couldn't pull any codes with that wire disconnected is because the ECM didn't have any power.

The reason the idle jumped up is because the ECM controls the timing. If you're running with that disconnected, you're running with full rich on the primaries and a FLAT timing curve all the time.

You'll need to reconnect the wire and have the car tuned with the ECM connected. My guess is your base timing is set way too high to compensate for a lack of timing advance.

BTW--as a general rule, if you have a check engine light, you have (or are supposed to have) a computer. All 82-92 Camaros produced for sale in the US were computer controlled. However, some of the early year cars sold in Canada were not. You can easily tell if you have a computerized carb by looking at the electrical connectors on it. The passenger's side will have two: a single blade connector for the electric choke on the side and a two wire blue connector on the top for the mixture control solenoid. The driver's side will have a single three wire connector sticking out of the front corner for the throttle position sensor.

Computer controlled carb:


Non-computer carbs will have at most one connector (the electric choke). Some utilize a hot air choke and have none.

 

Thanks for the replys.They were very helpful.I bought the car just like that.So i didn't want to touch anything.I guess 99hawk120 is right.Cuz the car runs really rich.It was worst before.But it got better since i've changed the air filter.But it still runs rich.I can tell by the smell.Is there a way to set the timing by myself?Do you think if driving like that damages the engine.I don't really have any experience on V8 engines.Actually this is my first V8.I hope i'll get better with time. Thanks again.

 

To set the base timing, first reconnect the ECM connector. At that point my guess is the idle should jump up to the 2000rpm you keep seeing, and the check engine light should go out.

Then locate the 4 wire weatherpack connector near the distributor. If you can't find it, try tracing the wires from the distributor. Disconnect that connector. The engine should drop back down to a low idle. It might not be the same as it was before because the ECM is still controlling the fuel (via the mixture control solenoid). At this point the Check Engine should also come back on.

Use a timing light to set the base timing. I can't tell you off the top of my head what it's supposed to be, since I use a bit more of a "shadetree" way of setting the timing (which involves having a scan tool). It's probably somewhere between 0 and 10 degrees. I'm sure someone else can chime in with the correct value.

Once the timing has been set, reconnect the four wire connector and turn off the car. Disconnect the "evil orange wire" for a few moments to clear the ECM, then reconnect it and start the car. The idle should be much more reasonable.

You may have to adjust the idle mixture screws on the carb next, but I'd get the timing set to factory specs first.

 

I already replaced the alternator this morning.I replugged the wire and everything was normal.The rpm was at the normal operating range around 1000 rpm and check the engine light is gone.I really don't know how that happened.But it works now without setting the timing.Now i can enjoy my trans am at last.Thanks for the answers.I appreciate it

 

Tongi,

I recall one of your earlier posts on this topic. What ever happened to adjusting the M/C solenoid? As I recall, we determined that you have an ECM based on the fact that your carb is an E4ME. You need to keep that wire connected and reset the base timing, TPS, mixture control, high idle, and curb idle.

Obviously, somewhere along the line someone was "confused" by the ECM and tried to bypass it. You need to "undo" their ignorance and repair the real problem.

 

Vader last time you asked me the color of the wire.Then i replied but you never answered.But in my reply i wrote that the wire was black.It was wrong.Anyway right now my biggest problem is gone.I'm sure i'll find some more absurd stuff on this car.So i'm sure i'm gonna need yor help again.It was little bit late (few seconds) but thanks for the reply.