Misfire Ford Windstar with the 3.8-litre engine
This problem may be easier to diagnose than to repair. The exhaust gas recirculation (EGR) valve meters exhaust flow from the exhaust pipe to the intake manifold. From there, the exhaust flows through a small orifice at each individual intake port. Carbon buildup can block off these orifices. When that happens, the excess exhaust gas flows into other cylinders, causing misfires. To determine whether the misfires are EGR related, simply unplug the vacuum hose running to the EGR valve. Plug the vacuum hose and take the van for a test drive. If the misfire disappears, you’ve got plugged orifices. That’s the good news. The bad news is that you have to remove the lower intake manifold and manually clean the orifices to correct the problem. If the problem doesn’t go away after unplugging the EGR valve, perform a wet and dry compression test, test the crankshaft and camshaft position sensors and the ignition coils .
© 2012 Rick MuscoplatPosted on by Rick Muscoplat