I think that the 104 is one of the best engines. The wire harness will be replaced under a goodwill for 120k miles at our local dealer. The have done hundreds for us...As for the head gasket, yes, one in 3 will fail early, especially if the engine has ever been run at all hot or has not had coolant changes....
Other than that, they do not go through valve jobs or use oil, they have alot of power...
I think that the few problems that they had can be overcome and you get a great package.
1991 GMC Syclone
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