Honeywell owns Autolite and the autolite factory in Ohio makes motorcraft spark plugs so they are fine to use if motorcraft aren't available, but they are not the same as motorcraft.
OEM factories build parts to the specifications of the company that orders the parts, in the case of Motorcraft they are built to Ford specs, Autolite may choose to use the same specs, if they are allowed too, or alter them because of cost or.........??
And because of Fords coil pack and waste spark system no matter what brand you use it should be Double Platinum if you want them to last.
P0141 Ford - O2 Heater Circuit Bank 1 Sensor 2
Sensor 2 is the sensor behind the Cat converter, and P0141 usually means a wire is bad or fuse is blown.
O2 sensor has 4 wires, 2 are for computer and 2 for the heater circuit which is fused in engine bay fuse box.
O2 sensors are heated so they can be used sooner, they need to be above 600degF to read oxygen levels.
Sensor 2 is used to monitor if the Cat Converter is working, it isn't used in trimming air:fuel ratios, so won't effect engine operation.
Sensor 1's are near the engine, "upstream sensors", these are used for air:fuel trims.
Does it run OK at higher speeds, RPMs?
If not check fuel pressure, should be 65-70psi on a '00 Ranger when running, increase RPM to approx. 2,000rpms and hold it there while watching fuel pressure, it should stay above 60psi.
Shut off engine and watch pressure, it should hold above 55psi........basically forever.
If pressure starts to drop then you could have leaking injector or bad fuel pump check valve.
After engine is warmed up, unplug IAC(idle air control) valve, it will close and idle should drop to 500rpms or engine may even stall, either is good because that means no vacuum leaks.
If idle stays above 700rpms then you have a vacuum leak.
Double check firing order on coil pack, I mess that up every now and then, either at the coil or at the spark plugs
I know you know it is correct, so did I every time it wasn't, lol.
So trace each wire from coil to spark plug.
Last edited by RonD; 04-24-2015 at 10:57 AM.