Cylinder 1 2 misfiring
I have a `75 FJ40 with a stock engine except for a Mallory distributor and a Webber carb. I have replaced the points, cap, rotor, plugs and checked the wires and coil as per the repair manual. The compression is great and I verified the timing is correct.
I failed an emission test due to high hydrocarbons and I think this is due to misfire. I can feel the truck misfire and when I pull off plug #1 and #2 the engine slows down a little but not much compared to when I pull off plug #3, 4, 5, or 6. I verified that all the plugs are getting good spark. I thought maybe there was a vacuum leak forward of the carburetor (that feeds #1 and #2) but I can' find one. Anyone have any ideas as to why my engine might be misfiring? I also suspect that all cylinders are misfiring and just more noticeable on #1 and #2.