my 1999 ford escort reads po1506 po171 and po0302

Question

the obd says cylinder 2 misfires replaced spark plugs, wires, and injector at cylinder 2. I also ran a can of seafoam through gas tank. idle is rough and doesn't get going very well

Answer 1

P1506 Vehicle speed sensor (VSS) intermittent

P0171 Fuel trim lean  Bank 1

P0302 Misfire number 2 cylinder

The need for a mechanical check has to be done, such as the compression or even a leak down test performed at the cylinder. Another area to check is the intake manifold gasket for any vacuum especially at the number 2 cylinder area.