I was driving just cruzin when my tach dial started to flicker then go back down. In the same time I felt as though the engine stalled. This occurred several times but then the problem went away. Today it happened again, now when I start my car the rpm goes up and down and almost stalls. What could be the problem...the alternator, my spark plugs, spark plug wires???????HELP!!!!!

 

Failing plugs or a faulty alternator usually don;t create those symptoms. The battery will still run the engine for a long time after the alternator fails. And one or more failing plugs won't kill the entire ignition system and "flake out" the tach. You likely have an electrical problem with the ignition primary wiring.

Check the connections at the distributor. Check the wiring at the starter positive power node. Look at the HEI module connectors and ground. If you have a separate ignition coil, check those connections as well.

Don't overlook the aftermarket ignition box, either.

 

Thanks for the tip Vader. I've disconnected the MSD and the problem still exist. This morning I started the car and the idle went up and down and almost bogged out. After a few revs and 5 minutes later, the idle went back to normal. Ive changed the spark plugs, distributor and rotor, plus the fuel filter, but still the rough idle. I aslo changed the IAC valve. NOCANDO!!!!.... What could the proble be.....Vacuum leak??????