Heres the deal my car idles nice. But when i accelerate in idle, the rpm needle bounces erratically.
This also happens when the car is in gear. The problem started when i changed my cap, rotor, and the wires. I drove the car half a block and it died. So i changed the ignition module and the capacitor and the car started up. Then thats when the bouncing rpms started. thats why i think the problem might be electrical. or maybe it was just coinsidence. Any ideas would be appreciated.
82 z28 305

 

Now i dont know too much about the ignition system in cars, but if theres one thing i do know its electronics, if the tach is bouncing after you replaced the capacitor, i would look towards that first. It sounds like the capacitor isnt sending the correct amount of electricity to the tachometer. Try putting the old one back in and see if it does the same thing.

 

Well first of all thanks for the suggestion. I installed the old capacitor back and the problem is still there.
The wierd thing is that with the old capacitor the car will turn off if when i rev it. And with the new capacitor i can rev it up to 35rpms before the tach gets to bouncing. Im ar a lost i dont know what else i can check or do to get this problem fixed. I really need my car for work. (public transportation blows)
Any other suggestions? Anyone?

 

i had the same dam problem in my 95 z28 couldnt find the problem but we think we got it with replaceing the optispark, i replaced a ton of **** before that so idk if that in a 82 but just thought i would tell u since ur havin the same problem...

 

The capacitor on the fire wall is just a noise filter. Its not even needed. I am assuming you still have the HEI. Your tach wire is one that goes into the cap. It just pics up its signal from the coil (negative side) Make sure the wires are good and the connection there is good. The negative side of the coil also gives a signal to the ignition so if its running then it may just be a bad connectin.
And did you also put the ground strap thing back in the cap that one of the coil hold down screws go on?