[AstroLover]

My 1993 has 178,000 and change. I have replace the Central Multiport Fuel Injection Unit twice. In MN we have gasoline that has been modified and this causes the Fuel Injection Unit to develope leakage in the regulator portion I beleive. GM has redisigned the unit several times and therefore there are three or four part numbers. The old part numbers may still be sold in the gray market through some Delco channels but officially the GM parts center should be selling only the up-level ones. The symptoms are rough idle, hunting of the idle, poor fuel economy and funny smell when running. Also, when you start the vehicle, it may take extra cranking to get it to start. Another common problem on these I'm told are the fuel tubes that are inside the plenum on top of the intake manifold get leaks from rubbing together. My friend is an ASE Master Certified mechanic and has noted both these as common troubles. One easy way to check it is to do a fuel pressure test and BE CAREFUL as the fuel can leak from the connections while attaching and disconnecting the pressure guage which is a special tool but well worth the cost. I beleive my pressure runs at about 55 to 60lbs and when you turn off the van, it may leak down a bit but it should hold if the CMFI, lines and fuel pump are OK. The symptoms are all variable depending on how bad the failure is. Bad news is if you do this yourself the parts alone are $500.00 or more. Good Luck...