Could this be on due to the cats being removed? O2 still hooked up, but I smell exhaust in cab. Are there air tubes near the rear of the intake on this truck> Rain here, havent had much chance to get out there to even look at it. Runs rough seems rich...

 

The light comes on only based on a timer. There is a module under the dash board above the gas pedal that you can unplug to get the light out permanently. You can reset the timer with a screwdriver, but the light will just come right back on when the time is reached again. I can't really give you more detailed info right now because it's been 6 years or so since I unplugged the module on my truck. I think I found the reset procedure in my Haynes manual, so that should be able to lead you to the correct module.

In short, the light is not due to any of the problems or symptoms you mentioned. You can pull the codes from the engine computer to see if there are any problems noted there. Search google for "eec-iv self test" and follow the instructions to find the codes yourself.

 

I bet 1 or more of your O2 sensors went out pull them out and check them or if you have OBD II you can just rent a code checker from Autozone and check them that way. If you have OBD I go to http://www.fordfuelinjection.com/ to see how to do a self diagnostic test.

BTW thats good advice EPNCSU2006 because forgetting the problem makes it go away.

 

Does a bad O2 sensor cause intermittent problems? FOr example, on the way to work this AM, it was hesitating and stumbling. At the first stop light, I took off and it was smoooth as glass. Two lights later, hesitating and stumbling again. Three lights later, smooth, etc. Can teh O2 give intermittent problems like this?

 

I said nothing about forgetting the problem, and all the info I've given is correct. If you'll read the last bit of my post, I actually advised pulling codes from the engine computer to see if it has any codes stored related to the problem. That's hardly forgetting problems. The EMISS light (NOT the same as Check Engine) on these older trucks (only 87 I believe, maybe 88's too) has absolutely no diagnostic aspect at all--it comes on simply based on a timer. If you reset the timer, the light will be on in another 80000 miles or so. Since you obviously do not have one of these lights in your '95 and obviously don't know what you are talking about, I think you should not criticize the advice I have given. Do some research before calling someone out next time...

Dragford, the symptoms you have listed don't jump out to me as an O2 sensor problem. It could be, but check the codes to see if there is anything definitive there before you throw any parts at it (that can get expensive in a hurry). You can follow the instructions at fordfuelinjection.com like was suggested by zemus, or since your check engine light is probably not wired, I would go to google and search for "eec-iv self test" and follow the instructions to pull codes with a test light or an analog volt meter.

 

The right way to reset the Extended Useful Life Sensor per Ford:

To find the module:

It is a little black plastic module behind the dashboard located on a metal bracket between the steering column and the windshield wiper switch. Looks about 1 inch wide, 2 inches tall, and connector on the top. It is solidly mounted to a bracket with a couple of screws, so it can be removed to make things easier.

To see it, you will need to rig the door so that the dome lights/foot lights do not come on - if you don't you will look right into a burning lamp.

Take a flashlight and hand mirror to find it. With the mirror up under dashboard on left side of steering column, shine light into mirror toward the backside of panel.. You should see the module. You will not see any hole or reset label on the side you can see. It is on the side of the module away from the steering column, near the top. I saw what looks like a white blob of paint, says reset under it. My guess is that you punch through the white blob with the Phillips screwdriver. Doesn't look too easy, you may need someone to help with the ignition switch part that follows.

Here are the exact Ford instructions:

Step 1. Turn ignition keyswitch to Off position

Step 2. Lightly push a Phillips screwdriver through the 0.2 inch diameter hole with the sticker labeled "RESET" and lightly press down and hold. Go to Step 3

Step 3. With the screwdriver still pressing down, turn ignition switch to the RUN position. The EMW lamp will then light and should remain lighted for as long as screwdriver is pressed down. Hold the screwdriver down for 5 seconds. Go to Step 4.

Step 4. Remove the screwdriver The lamp should go out in 2 to 5 seconds indicating a reset has occurred.. If not, start over at step 1. Turn the ignition switch to OFF and go to step 5.

Step 5. Turn the ignition to the RUN position. EMW Lamp should go off in 2 to 5 seconds. If not, repeat the procedure.
The book also says that some modules do not have the reset hole, and would need to be replaced. Removing the connector will also turn off the light.

Note that there is also a device called “The Inferred Mileage Sensor” and it is not the same thing as “The Extended Useful Life Sensor” but may be in the same enclosure in some trucks.

 

It ain't a truck, but the '86 T-Bird's used a digital Odo/Speedo, and turned on the SERVICE indicator in the speedo module every 17000 miles. This was basically your warning to change the fluid in the C3 after dragging a 3900 pound car around with a tranny that was designed for much lighter cars.

I'm guessing the older trucks used a timer instead? What drives the timer, or is it a pulse counter arrangment using the speedo drive? Does the 87/88 vintage use electronic or cable driven speedo?

I have a '92, so not affected by the problem, but find it to be more interesting stuff to clutter my brain with.

dragford, listen to EPCN and subford. They both are very knowlegeable, and subford seems to be in possession of every Ford service manual ever printed. ;D

 

The 87 speedo is mechanical. I couldn't tell you if the timer is mileage based in any way or if it just calculates a run time.

In my opinion, resetting the light is just going to cause it to come back on again in the future, at which time you will do nothing but reset it again anyway, so why not unplug it now and be done with it? All it does is turn on a light after a preset amount of time, so why not?

I've re-used the pin feeding that light to actually connect the circuit that feeds the spot in the dash where the Check Engine light should be and attached that wire to the STO output of the computer to make it work like it should. I still can't figure out why Ford didn't wire the Check Engine light on the 87's.

Sorry if I came across as being rude earlier....

 

You? Rude? Naaaaaaaah.

I don't take this stuff personally.

Now that mod with the STO to hook up a light on the dash would be a good mod to post for others (assuming you haven't already done so) with 88 and older trucks.

 

I haven't posted anything about hooking up the STO wire. I hadn't really thought about doing so, so I'm not really sure where or how to go about doing that.

 

DragFord,

I believe you failed to mention what year truck was. On most Fords I believe they had an air pump which either Pumped fresh air into your "cat" or your exuast manifolds or possibly even both to lower emissions. I think that when you pulled your cats, you opened this system up and now have a small exuast leak.

As far as your stumbling goes, seems more like a low voltage condition on your TPS, but also could be your IAC, or Water tempature sensor.

One good indiacator on O2 sensors going out is the engine will stall (exspecially a standard trans truck) or it will "peg" your tack at 6000 RPM's. also your gas milage should suffer enuff that you notice it.

Best bet is to pull codes like mentioned above.

 

I've never had this occur and never heard of either symptom. The O2 sensor shouldn't have anything to do with what rpm the engine runs, except possibly idle speed. I've run with the O2 sensor completely disconnnected and never noticed any big driveability problems.

 

Umm, I'm replying to #10 in this thread, which was I think a reply to my #9, which was a reply to your #8. Was this not you?

To quote you (or at least a message with your username and signature on it) again:

This is what I was talking about.

 

I meant it differently...I should have used another word besides post so as to not confuse everyone. I haven't submitted any kind of write-up for the "help" section or created a thread on how to do this, mainly because I never thought of doing so. You made a good suggestion, so now I'll have to figure out a way to easily instruct people how to re-wire this to make it work.

 

LOL, Eric.

Ain't it funny how we get "volunteered" for things?

I gotta call Justin tomorrow to find out how to submit an article.

Look forward to seeing the article. Might be useful on the old Duck too.