If anyone out there would be so kind as = to send me some info on idle adjustment problems. I just replaced all major = engine gaskets, had the heads checked out, replaced the water pump, piston = rings, thermostat, fan switch, and etc. Yet I am having idling = problems. It idles at around 400 - 500 rpms, and is unresponsive to adjustments of = the idle screw. I checked out the fuel injectors (pulled the plug off each = one and listened for a drop in idle) on the number 2 cylinder there was no = effect on idle when the plug was pulled. I switched the injector with a = good one and the effect was the same. The idle seems to be "seeking". = Could a faulty coolant temperature sensor or leaky exhaust system be causing the = idle to act up? Does the O2 sensor play a major role in the idle = function? I also noticed the oil pressure switch is leaking pretty badly. = Also, I did replace the plugs and cap and rotor. It almost seems to be running = on three cylinders, and the problem only gets worse as the van heats = up. Thanks for taking a look into this!