I just replaced the intake manifold gasket on my 92 Chevrolet Silverado with a 4.3 it is now sluggish and does not want to start what did I do wrong?

Was it running normally before these repairs? If so, double check everything done to ensure all was restored properly. I can't really advise much without hands on testing, so recheck all you can -- but -- Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops