I was told that I had fuel in my oil and the only way that would happen is a fuel management part under the manifold.is this true? if so what is the name of the part. ive taken it to a mechanic who replaced all my plugs, wires ,and egr valve and some kind of fuel management part my truck starts but is undrivable im not sure what fuel management part or whatever he put in but $500 later he said he coulnd't fix it. I really like my blazer and want it to run right again someone plz help

*edit*
sorry it is a 1994 gmc jimmy blazer 4.3 vortex engine


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