My cruiser had been having some horrible idle and acceleration issues for 2 weeks. I just recently replaced injectors in late winter and now it has the same stumble and idle. I went in just this weekend to replace the injectors again, but after, the idle was the same irregularity and now the manifold, which I didn't know had an exhaust leak also leaks oil. The 92 80 series with the 4.0 has a split exhaust manifold between cylinder 1,2,3 and the other one 4,5, and 6. Thinking valves seals but would they put out that my oil