Please I really need help with a 1991 C1500 Chevrolet Silverado
 

Hi i am new hear and i am just 17 years old but i am really seeking help. y dad just gave me his 1991 Chevy Silverado but everytime i turn it on it begins to emmit a black/blue smoke from the exhaust. I really do not know what the problem is, my dad believes that it might be a sensor but i do not know. I really need help repairing the truck to continue attending school and my job, however, unfortunatly i do not have a budget to take it to a shop and are really interested in fixing it myself. Thank you to anyone who is willing to provide help.

RE: Please I really need help with a 1991 C1500 Chevrolet Silverado
 

if its has thottle body injection, it can be the o2 sensor going out..

RE: Please I really need help with a 1991 C1500 Chevrolet Silverado
 

another idea you can try is check the timing or see if you can get the codes the computer is sending

RE: Please I really need help with a 1991 C1500 Chevrolet Silverado
 

if it only does it at startup I would think the valve seals are worn and oil is getting past them. Thus the smoking at startup. Does it smoke all the time or only at startup?