I can't understand what you're describing if you're too lazy to put a simple period in there once in a while. I'm no English expert either but at least I can make my descriptions understandable. Here's how your description can be interpreted: "i have a 84 corvette my car runs real rough and having troubel with my charging systems". "Having troubel with my charging systems when the car is running". "When the car is running it runs real rough". "When I remove the negative cabel the car runs smooth and my charge light goes off". "It runs real rough when I remove the negative cabel".
So, as near as I can tell the engine runs smooth or rough when you remove the battery cable. I don't know which one is correct and you have no desire to tell me. What I can share is it is not a good idea to remove a battery cable while the engine is running. If the generator is working properly, doing so can allow system voltage to go very high, especially if you raise engine speed. On a 1984 model you might only pop a few light bulbs, but on newer cars the many silly computers can be damaged. A better test is to use an inexpensive digital voltmeter to measure battery voltage while the engine is running. You must find between 13.75 and 14.75 volts. If it is low, there is a "D" hole on the back of the generator to allow you to bypass the internal voltage regulator to see if it is defective. Don't raise engine speed very much during that test because system voltage can again go too high. Stick a small screwdriver into the hole until it touches the test tab, then move it sideways to also touch the housing. If it starts charging and the warning light goes off, the regulator must be replaced. Your generator is fairly easy to disassemble to replace parts. It's the second best design in the world, ... Certainly a lot better than the very poor design they started using in 1987.
If there is one shorted diode in the generator it will cause excessive ripple which can affect your Engine Computer. The same is true of the "diode trio". If either of those diodes is defective the warning light will be on dim. That ripple will also affect the signals coming from the engine sensors. If the rough running is caused by the generator, it will smooth out when you unplug the two-wire connector while the engine is running.
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Monday, March 7th, 2011 AT 2:30 AM