1998 GMC 1500 SLT
My 1998 GMC 1500 SLT with a 350 engine in it. It was
sitting for a while. When I first started driving it it was doing
fine until after about 2 hours of drive time. My gauges are
all inaccurate. I was told that a line could be clogged. I just
don't know what to do. I put antifreeze inside it, but it just
blows it out. Thank you in advance.