02 sensor

[1986F150Six]

I have seen some early 2 wire sensors, signal and ground, right now can't remember what they were on, may have been GM stuff. Your Bronco in the 1986 EVTM shows a 2 wire sensor, DG/P for the signal to pin #29 of the EEC and O to pin #49 as a signal ground. The 4.9L shows the same wiring, but the 5.8L does not use the ground with the feedback carburetor. It does have a ground wire (O) at pin #49 to the engine.

Is this one of the 2 wire sensors, Bill?

[E6TZ-9F472-A]

https://www.ebay.com/itm/Vintage-Genuine-Ford-NOS-Ranger-F150-Oxygen-sensor/133365939674?epid=23011282917&hash=item1f0d3abdda:g:pssAAOSwhQheYW4I

Edit: I just noticed a 3rd wire [black].

 

[old55pete]

Ok, I have a question, did you transplant the entire harness, or just the engine part of the EFI harness? The reason I ask, is there are major changes in the EEC plug between 1986 and 1987. Power and ground were part of that pinouts for the EECs (actually everything I could find including EEC-III and the MCU systems) are here: http://www.garysgaragemahal.com/efi.html The 1985.5 and 1986 are the only truck systems that used the vacuum and vent control on the EGR and for some reason the MAP sensor was different, but the later ones seem to work ok on them.

Bill, at first I got mad and started deleting posts and was going to drop out of this group as I have done so on many others. Most of these sites are now defunct because of the in fighting, folks talking down to each other, name calling and the ever present, YOU CANT DO THAT BECAUSE...……….

I had planned to not come back because I dident want to end up stuck in the middle of another YOU CANT DO THAT BECAUSE...………… From someone that dident do the total research to see if it was even feasible to do or not. I did a lot of exhausting research, pouring over wiring diagram from both the 86/ 87 Broncos and F100/ 150 5.0 EFI. I spent the time going over the EVTM's of both and found out it was posable.

One of the things that I found is that the wire color codes were the same from 85 1/2 to 96 , with very few differences. One of the things that was different was the plug to the ECM. When the rats chewed the harness out of my Bronco, they left, in most cases, around six inch tails at the firewall and the sensors and relays. I soldered my plug to the 87 harness omitting the wires that I dident need and moving the wires to the proper pin. For example, Pin 5, wire 361,bk/ltg-d, circuit 60, ground in the 86, not used in the 87. In the 87 harness pin 5 is not used, but pin 6, wire 57, blk/ltg is also circuit 60, a ground. Another example, pin 52 is not used in the 87, but it is in the 86. so you add the purple wire to the harness...….. I am pretty sure that you know where I am going with this.

The one thing I did screw up on was the O2 sensor, The one in the 87 was a three wire( Ford calls it a two wire, Don't ask cause I dont know why) and I took it and put it in my 86. It ran but with a hunting idle, kept going rich then lean and was cycling the EGR on and off. That was when I started this on here about the O2 sensor. Gary then showed me how to use the calibration code. I found out that I needed a one wire sensor and had to pull the harness and re do the wiring to use the one wire sensor and put in the correct O2 sensor in and that cleared the symptoms and the codes.

I don't want to leave this site as there is way to much good information here. There is a lot of good folks here with some great Ideas that were a big help to me when I first started out. I stated it before and will say it again, I am a diesel/ heavy equipment mechanic and I know a lot, but I do not know it all and like any good mechanic, I need help too.

Bill, if you have any other questions, make sure to ask them and I will do my best to answer them.

[85lebaront2]

Bill, at first I got mad and started deleting posts and was going to drop out of this group as I have done so on many others. Most of these sites are now defunct because of the in fighting, folks talking down to each other, name calling and the ever present, YOU CANT DO THAT BECAUSE...……….

I had planned to not come back because I dident want to end up stuck in the middle of another YOU CANT DO THAT BECAUSE...………… From someone that dident do the total research to see if it was even feasible to do or not. I did a lot of exhausting research, pouring over wiring diagram from both the 86/ 87 Broncos and F100/ 150 5.0 EFI. I spent the time going over the EVTM's of both and found out it was posable.

One of the things that I found is that the wire color codes were the same from 85 1/2 to 96 , with very few differences. One of the things that was different was the plug to the ECM. When the rats chewed the harness out of my Bronco, they left, in most cases, around six inch tails at the firewall and the sensors and relays. I soldered my plug to the 87 harness omitting the wires that I dident need and moving the wires to the proper pin. For example, Pin 5, wire 361,bk/ltg-d, circuit 60, ground in the 86, not used in the 87. In the 87 harness pin 5 is not used, but pin 6, wire 57, blk/ltg is also circuit 60, a ground. Another example, pin 52 is not used in the 87, but it is in the 86. so you add the purple wire to the harness...….. I am pretty sure that you know where I am going with this.

The one thing I did screw up on was the O2 sensor, The one in the 87 was a three wire( Ford calls it a two wire, Don't ask cause I dont know why) and I took it and put it in my 86. It ran but with a hunting idle, kept going rich then lean and was cycling the EGR on and off. That was when I started this on here about the O2 sensor. Gary then showed me how to use the calibration code. I found out that I needed a one wire sensor and had to pull the harness and re do the wiring to use the one wire sensor and put in the correct O2 sensor in and that cleared the symptoms and the codes.

I don't want to leave this site as there is way to much good information here. There is a lot of good folks here with some great Ideas that were a big help to me when I first started out. I stated it before and will say it again, I am a diesel/ heavy equipment mechanic and I know a lot, but I do not know it all and like any good mechanic, I need help too.

Bill, if you have any other questions, make sure to ask them and I will do my best to answer them.

First item, your apology is accepted, I generally will not get in an argument with someone, I will try to the best of my ability to explain how things are supposed to work. If someone wants to get in a pissing contest with my, I will let them go their merry way, there was one on FTE a few years ago having issues with a Quadrajet on a Ford engine, FWIW, 1970-71 429 CJ engines came with them, the SCJ had a Holley.

I was trying to walk through his issue and got told in so many words I didn't know what I was talking about. so I left the thread, I monitored it for a few days, and after several people (Gary may have been one) told him he had probably just pissed off the one person who could help him (problem was 4 cyls pig rich), he begged me to please come back. I told him to carefully remove the top and look at his primary metering rods, sure enough he had bent one when he missed the jet.

Ok, lets see if I understand (a) what you have done and (b) some suggestions.

(a) you have an early (1985.5-1986) EFI 302 engine. You have not clearly defined what year EEC you are using. You have chased down the wiring differences between 1986-1987 and from what I gather are using the 1985.5-1986 EEC. Technically, as near as I can tell, when Ford says a 1, 2, 3 or 4 wire O2 sensor, it is 1 is signal 2 are signal & ground (orange) 3 are signal and heater (white wires) 4 are signal, ground & heater (usually gray, black and white). The reason the heated O2 sensor didn't work correctly, no heater so It could not respond properly. Question, are you still using the rear of the right exhaust manifold for the O2 sensor, or are you using the later location (in the Y pipe)? If it is in the Y pipe, you will need to have a heated sensor for proper response, wiring the heater in is easy, it uses the purple/orange wire (backup lamps feed) as a power source, the other side is grounded.

One of the early mistakes Detroit made when heated O2 sensors first came out, was to use the same ground wire for heater and signal grounds, this caused problems if there was too much resistance in the ground circuit. If you are using the later EEC, a few items, pin relocation you have covered, EGR control, 1985.5-1986 use two solenoids, vacuum and vent, 1987 up use a single "duty cycle" combined vacuum and vent valve. 1985.5-1986 do not use a speed sensor, 1987 up do. 1985.5-1986 throttle position sensor, is extremely sensitive and touchy, if you have to change it, bite the bullet and get a Motorcraft one, we fought a surging idle issue on my son's 1986 F150 until he finally bought a Motorcraft sensor. The idle setting is based on the TPS reading of 1 +/- .1 volts, the aftermarket one would not go below 1.15 volts at fully closed throttle. 1987 up, the EEC looks at the closed throttle reading and uses it for control.

BTW, I am a trained Diesel mechanic, Detroit Diesels in the Marines, Mercedes-Benz Diesels at the local dealer in Hampton VA and owned several GM 5.7L Diesels.