you could do it with a voltmeter, disconnect the O2 hook the + lead to the wire on the O2 and the - on the case of the O2, voltage should be between .1v and .9v and should rise when you snap throttle.
the O2 also grounds through the exhaust so if there is a lot of rust around the O2 and or exhaust connections to the motor it may not work right, also look for exhaust leaks before the O2.
ok the fuel injection system is in open loop (means its not tuning it self off the o2 sensor) for about the first 2 to 3 min when the motor is first started. after that when the motor idles, and is cruiseing its tuning it self by looking the o2 sensors. when you floor it, the computer goes back into open loop and is running on preprogamed values that have a correction factor applyed that is figured out from the closed loop operation time. now that you have said that its ok during the open loop times and seems to have its problem during the closed loop periods, i would be looking at the o2 sensors and there related wireing. i have seen the wireing harness melt on the exhast and cause all kinds of problems. the o2 sensors do not use the exhast for ground they have a ground wire. this wire is the ground wire the comes out of the harness behind the drives side cylnderhead. it bolts to the back of the driver side cylinder head. i would take that ground wire off and clean up the surface that it mounts to with sandpaper. then put it back on and see if it helps.
some O2 sensors have only 1 wire, and ground through the exhaust. if it has 2 wires then it grounds through the cylinder head like you said. if it has more then 2 it's a heated sensor and probably grounds through the cylinder head.
yes, when ford put fuel injection on in 86 they had 4 wire o2s. i think that ford used 4 wire o2s on all there efi systems as long as it wasnt another make of car rebadged as a ford
Bryant mine already has the new plug you spoke about on the back on the intake, just seen them. Going to buy a set of new ford racing 9mm wire and a new cap and button. My buddys seems to think my wires might be missfiring. Heres what he did today. He had another distribator so he change it out, and he changed the timing, also put a different cap and coil on it. Timing was 7 degrees and he changed it to 12. That mad all the difference in the world motor cam to life. Its still has a little miss, untill you get on it. But im much happyer than i was. At least you can drive it now...........
