alternator belt?
 

ok im sure i have a bad alt. belt or its at least loose because in the morning when its cold it squeels and w/e else but when im driving sometimes my truck at 50 mph will all the sudden missfire or lurch or somthing like that and occasionaly when im ideling the rpm will go down to about 400 and then jump up to 800 and back and forth and it happens at random times...the lights dim at the same time and i didnt have my stereo on at all so what do u guys think is it a quick alt. belt fix or somthing worse sadly i have to drive it in the mean time

RE: alternator belt?
 

Disconnect your battery while your car is on and if your car shuts off you need a new alt. Thats all that I can help with. I hope it will something simple goodluck.

RE: alternator belt?
 

ok i talked to my g-pa (a former chevy mechanic and he said it was most likely a bad tank of gas that went through and or my fuel injectors need to be cleaned so i should run some cleaner through my next tank of gas he also said i should get a new belt and see how it runs afterwords....he said if that doesnt fix it it could be an egr valve [:@]:(............what do u guys think