1986 2.3 / 4 cyl. Ford Ranger

Hello out there in Ford Cyberspace!

I am going to get a Smog test for my 1986 2.3 / 4 cyl. Ford Ranger.
Two years ago, I had to replace my oxygen O2 Sensor and replaced a cracked Exhaust manifold and then the smog passed.

Today, I was looking under my engine and noticed a wire dangling from the O2 sensor. It looks like it could be extra wire,tied in a knot about 9 inches long, but the lead of the wire is exposed and I was wondering if this is normal. (maybe so maybe no) I will get a closer look tomorrow,but thought I'd ask tonight. I have no clue where this wire should plug into. I think the sensor comes out of the engine,breaks off in to two wires,then this one might be extra. I just had an Oil change and was thinking Maybe something happened at the shop. Thanks for any info or help.

 

Perhaps you got a 'generic' O2 sensor, and it had a heating element that is not used on your application. Translated, some O2 sensors have a heating element embedded so that they reach operating temp sooner, and thus can go into closed loop sooner. Your original may have not been equipped with a heater (I doubt it), so they just left the heating element unhooked.
If it passed smog test with it connected this way (hah), then it should be OK. When I got my Ranger in Dublin, CA, it failed smog on its first test. Failed second, freeby retest, too. Take to dealer. "we gotta test it to know it failed... We gotta clean the intake... It failed first and re-test. Take it to the referee. Oh, by the way, pay the smog test fee and the intake cleaning fee" I scheduled an appointment with the referee, where it failed again. Never did pass.
I hate smog tests.
tom

 

Thanks Tom!
I will look at the receipt on where I bought this sensor, and check it out. Thanks!

 

Whenever possible buy your sensors from Ford.

 

I've got the same truck, you should have two white wires and one black in your sensor wiring. to check if heater circuit is working just start it up cold in the morning, it should idle fast for two minutes then the sensor goes to closed loop and engine idle will drop. I also had to replace my exhaust manifold when i first got my truck two years ago. even though you live on the west coast like me consider blocking off about a third of your radiator to raise your engine operating temperature, you will get better gas mileage these engines are known for running too cold, should be between 190-195 degrees.

 

86' Ford Ranger EFI / 2.3 / 4-Cyl. / Manual Trans. / 2-wheel Dr./ 144,000

Hi you all'
Thanks for the replies. Well, today I went to get my Smog "Test only",worried about that loose wire coming from the Ford Flex Hose containing the fusible link to my oxygen Sensor. O 2 sensor passed, The ECS passed,PVC,EGR,Thermostatic Air Cleaner,Vacuum lines,sensors,switches,Ignition Timing(10 BTDC),Wiring to sensors,Fill pipe Restrictor,other emissions components, Carb/Fuel Injection,and Fuel Evaporative Controls...all passed..........
..........but the ASM Emissions Failed.

So, back to this "wire". I called FORD and they told me to bring it in for a diagnostic...sure, I have an extra couple hundred to throw away. They also said they did not know what that wire was without looking at it for a fee.
All I know is that my O2 Sensor,is plugged 1) into the engine, and the other end plugs into a (FORD) flex hose wiring harness composed of two wires,and this extra hose come out of the harness and just a loose wire,about a 16 or 18 gauge, and is about seven inches tied in a knot. It looked like it might have connected to something. Know one seems to know. The brake guy thought it might be a ground for the O2 sensor,but wasn't sure why that would not Pass the smog. He said he thought was an extra wire for the Original Ford O2 Sensor, ($145.00) but the Standard O2 one I bought didn't need it that wire.( $50.00) I replaced this O2 sensor back in 2002,where it has passed in 2002 and 2004.


I thought I covered everything,new air filter,gas cap,spark plugs,cables,ran it on the freeway at high speeds for an hour before taking it for the test. The only thing I did not do was to put premium gas in it.

High Hydrocarbons the guy told me. CO 2, HC(ppm), CO(%) and NO(ppm) RESULTS= FAIL.

Twenty year old car I would think I would be exempt by now. Far from an historical relic, but I think it still runs good for it's age.

What are some things I should be looking at as far as the emissions failing?

Thank you lots!!!!

 

your o2 sensor is disconnected, unplug it from the harness and look into the plug, it has three pins in it for three wires.

 

Dadzilla - About twenty years ago I used to live next to the bike trail near Vasona Park/Reservoir in Los Gatos..Beautiful Country!

Anyway, I went to the parts store today to have them pull off the shelf, the (Standard) O2 Sensor I bought four years ago,and I saw 4 pins inside the sensor to connect to the harness.
Would the O2 sensor have passed (as it did) the smog test, if it was dissconnected?

I will have to get a Chiltons repair manual and see more about this onboard harness that connects to the O2 sensor. Maybe the FORD O2 sensor has somewhere to connect to this harness, if only I spent an extra 100.00 through Ford. I usually swear by Ford's electronic parts,but couldn't afford this one four years ago,yet it passed Smog two years ago.
Tomorrow, I will pull the O2 sensor apart and see how may pins and wires.

Is there anyway I can take a picture and put it in a post?

Thanks a bunch!

 

Odds are that the O2 sensor will not cause the SMOG test failure you report. The O2 only 'trims' the fuel mixture when in closed loop (engine all warmed up, etc). If you got a Bosch brand O2, then it is as good as the FoMoCo. They supply a bunch, with someone else' name on them. The after-market SHOULD have exactly the same connections as the original. That is why they make so many versions.
With all readings high, you want to look at all the ppm numbers, and tell us what they are, along with the allowed limits. For example, I just tested a CA emissions ranger here in GA(low speed readings below).
HC ppm read:122 allowed:223
CO% read 0.32 allowed: 2.79
NOx read 1181 allowed 3135
RPM read 2274 allowed max 3000
CO+CO2 read 14.8 allowed 6.0 min
Generally, HC hi means unburnt fuel, implying misfire or extra fuel or plugged air cleaner
NOx hi means high combustion temp(disfunctional EGR), or a failing catalytic,
etc (i don't know all the etcs)
Ya gotta tell us the numbers...
FWIW, my 2.3 tends to gum up the intake (I assume it is PCV stuff... and EGR) leading to high HC (I think). If I squirt Gumout Carb cleaner (O2 safe!!) on and past the throttle body, and wash down the inside of the upper intake (the one that curves from horizontal to vertical) and let it sit for a while, or, better, remove the throttle plate altogether to be able to see the inside of the intake and wash it with carb cleaner, the truck runs smoother. This has gotten me thru the past several inspections, and this piggy NEVER passed the CA emissions test. This last time 2/14/2006, I did the gumout thing, checked the air filter, and removed and re-gapped the spark plugs (to .044, the middle of the range) and got the readings above. Way less than the limits, on a truck bought new December, 1984.... old enough to drink!
If you have high NOx readings, don't run it too far on the freeway as test prep, as it will make less NOx if a little cooler.
Really, if it runs well, and you have no codes, a clean air filter, recent oil change, good plugs & wires, it should pass the test. If your gas mileage seems low(around 25mpg for a 5-speed short bed is decent), you may have a failing fuel pressure regulator. That would send too much fuel, leading to high HC, even though it is firing well.
For more info on emissions testing, and interesting 'calculated' emissions checks, go to:
http://www.colostate.edu/NCVECS/index.html
and you can tell from the numbers if your catalytic is toast.. rather than the "mechanic" telling you 'cuz he "knows"...
tom

 

Thanks TomW,
Here are my ASM Emission results below, and I hope they will tell you something. My cat Converter EGR Functional and Visible passed,along with all the rest of the ECS Criteria. Just the numbers below seemed to FAIL.
As far as the Air Cleaner, I took it out and blew clean with a Air hose. I noticed how high the HC readings were..extremely higher than allowed. Could it be the Low regular unleaded gas? A few years ago I replaced the timing chain and did a compression check on all four valves and they appeared to be ok. , in-line fuel filter, fuel relay,etc.

Tom, Thanks for taking the time to look at this. I appreciate it. California emmissions are tougher than any other state.Thanks!

__________________________________________________ __
RPM =
15 Mph @ 2550 RPMS
25 Mph @ 2280 RPMS
__________________________________________________ __
% CO 2 read: (just measured, no Max. or Average)
15 mph test Read 14.4
25 mph test " 14.3
__________________________________________________ ___
HC ppm read: "
15 mph – 181 - Max. 139 - (Average for passing - 43)
25 mph - 182 - max. 111 - ( “ “ “ - 42)
__________________________________________________ ____
CO (%) read: "
15 mph Test - 1.56 - max. 0.96 - (Ave. 0.16)
25 mph test - 1.71 - max. 1.22 - ( “ 0.15)
__________________________________________________ ____
NO read: "
15 mph Test - 698 - max. 1113 - (Ave. 406)
25 mph test - 243 - max. 1176 - ( “ 348)
__________________________________________________ _____
% O2 read "
15 mph – 0.0 (just measured, no Max. or Average)
25 mph – 0.0
__________________________________________________ ________

 

One other little (or major) detail that slipped my mind this somog test,was that I forgot to replace the Disp.Cap and Rotor like I usulally do every smog test. I did replace all spark plugs .044 gap, New Spark plug cables,Gas Cap.

And two years ago a new distributor Coil .
Besides using cheap Arco gas (Reg. Unleaded) I guess I am doomed. If it's misfiring like you had mentioned,maybe it is the Cap/Rotor. Truck doesn't seem to shimmy and shake while idling.

 

You are getting too much fuel, in my guesstimation. Check your fuel pressure with a gauge. There most likely is a schrader (tire valve stem) connection on the fuel rail near the cam cover. A gauge showing too much pressure ( over 40 psi w/vacuum attached) indicates the regulator is not working. They ain't cheap.
If the pressure is OK, make sure that you have a fresh oil change, as old oil can be supplying dispersed gas fumes thru the PCV valve.
If you haven't done so yet, take off the big and small air tubes leading to the throttle. Remove hoses, throttle cable, and the 4 bolts (12 pt socket needed) holding the throttle body onto the upper intake. Get the gumout and douche the intake until it is clean. Let soak on the backsides of the closed intake valves (the liquid & gunk will fall onto them) for a while. Clean the throttle plate. Reassemble.
I bet you find the intake manifold coated with crud. The crud can be supplying extra HCs that evaporate out, and thus the hi HC reading. Given it is high at idle and road speed, I'd bet more on high fuel pressure or a leaky injector. If you do the pressure test, you should note the pressure after an overnight 'soak'. It should hold some pressure, and definitely should not drop to zero immediately after you turn off the key. If it drops, you have 3 possibilities. 1)leaky injector(s) 2) leaky return / pressure regulator 3)leaky anti-drainback valve in the fuel pump. If it is hard or slow to start in the AM, try turning the key to on, let the pump run & stop, turn key to off, and repeat for a few times to fully prime the fuel injectors. Then start the engine. If it starts good, better than average, it may be you have fuel pressure leakdown...
Lotta words. Read 'em a few times. Digest.
tom

 

Thanks Tom for all your input. Much appreciated. Fuel pressure regulator and carta lytic converter sounds suspect. If I can get to the other items and spray the gunk I will,but if I go and have it looked at, I'll let you know what and why the smog failed. Again, Thank you for all of your help.

 

You say that California's emmisions are the toughest to pass. I have one better than that for you. I used to have a car that passed emissions test in California. I brought it back to Georgia, Atlanta area, had it tested to get tags, and it failed Georgia's emission test. Seems that Georgia is tougher on the "NO" readings than even California is.

 

Wildman, the emissions specs follow the vehicle. In GA you still have to pass the CA specs if the car was built to Calif specs. My Ranger 'pass' numbers are the same here as they were in California.
tom