I have a question - where is the upstream Oxygen sensor located other than the downstream sensor at the exhaust manifold ? Or is the sensor at the exhaust manifold the upstream sensor and downstream sensor farther down the exhaust system ??
What can you guys tell me about these plastic intake manifolds ?? Good or Bad ? Gasket sealer or not ?? I would rather have a metal manifold but have to deal with this plastic one - first timer here with this manifold - thanks for the help here