91 Explorer Check Engine Light
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91 Explorer Check Engine Light
I have read the other posts about later model Explorer's check engine light problems. My light codes out to a 13(normal idle not within specified range) and 41 (oxygen sensor indicates lean condition),here in California as soon as the smog tech sees a engine light it all over and a automatic fail. Any ideas would be appreciated. Also my Haynes manual shows how to retrive the codes using a volt-ohm meter, is it different on the later models where you have to use a code reader?
Dan
Dan
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91 Explorer Check Engine Light
Somewhere during the '95 model year, I think, Ford (and everyone else) went to OBD-2 which uses letters as well as numbers in the codes. It's kind of difficult to get a needle sweep to indicate a letter.
I don't have any ideas for the 13, but the 41 may indicate a bad O2 sensor. The computer is seeing an abnormally low voltage from the O2 sensor. When my O2 sensor gave a lean code, it was because the O2 sensor had stopped reading and was constantly sending 0 volts. Before jumping to the conclusion that the O2 sensor is bad, make sure the connections are all good from the sensor to the computer. If that checks out, I would suggest replacing the O2 sensor. There are ways to check an O2 sensor, but the most sure way to know the O2 sensor is functioning properly is to put a new one in.
I don't have any ideas for the 13, but the 41 may indicate a bad O2 sensor. The computer is seeing an abnormally low voltage from the O2 sensor. When my O2 sensor gave a lean code, it was because the O2 sensor had stopped reading and was constantly sending 0 volts. Before jumping to the conclusion that the O2 sensor is bad, make sure the connections are all good from the sensor to the computer. If that checks out, I would suggest replacing the O2 sensor. There are ways to check an O2 sensor, but the most sure way to know the O2 sensor is functioning properly is to put a new one in.
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91 Explorer Check Engine Light
I'm not sure about the code 41.. but the Code 172 text for our 1992 is the same as the text for your code 41. (o2 sensor detects lean condition). If they are really the same thing, it is most likely the O2 sensor. It is a $42 part (not from the dealer) and very easy to change IF you have a suspension lift (maybe easy with a body lift also). I just use a 7/8th" combo wrench, disconnect the plug.. put the wrench on and I'm done in 10 minutes (I dont' have to lift the truck). If you still have your inner fenderwells you will need to remove it on the passenger side to get to the plug. I have found that if I crawl under the truck and put the wrench on it from the front (the wrench is above the exhaust cross over pipe) I can get to it easily.
I've had the code 172 twice and each time I change the o2 sensor (it happened about 60k miles apart) and it fixed the problem.
btw.. you may get the code 41 istead of code 172 since the 1992 X "might" have had 2 o2 sensors (ours only had 1) and the 172 is lean condition on bank 1 (the 1993 I believe had 2 sensors)
~Mark
I've had the code 172 twice and each time I change the o2 sensor (it happened about 60k miles apart) and it fixed the problem.
btw.. you may get the code 41 istead of code 172 since the 1992 X "might" have had 2 o2 sensors (ours only had 1) and the 172 is lean condition on bank 1 (the 1993 I believe had 2 sensors)
~Mark
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91 Explorer Check Engine Light
To MrShorty and the Maniac, Replacing the O2 sensor did the trick, thanks for the advice. It sure would be nice to be able to test those Sensors on or off the truck,would cut down on the trouble shooting time. But then FORD would not be able to charge you $80 an hour for doing the same thing any competent home car mechanic could do!!!
Dano14
Dano14
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91 Explorer Check Engine Light
Thanks for asking Hoppy. Yes it did, and i live in one of those wonderful Smog Check II areas. I guess it's time to buy some land in Northern California just to register my cars!!!
Dano14
Dano14
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91 Explorer Check Engine Light
I live in Ontario Canada and the government just started a "drive clean" program. Man does it suck. Now every two years we have to get our vehicles tested. They say that if you have a bigger engine other than what it originally equipped with it is considered a hot rod. What ever the heck that means?
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91 Explorer Check Engine Light
You CAN test an O2 sensor off the vehicle. You need to determine the correct wire for the signal (not the heater wire), and have a propane torch and good voltmeter.
Connect the signal wire to your voltmeter, should be an analog meter with at least 20K ohms/volt sensitivity. But in this case, you may be able to use a digital one.
The signal should be between 0.3 and 1.0 volts, after you get the tip( don't heat anything but the tip) red-hot with the torch. Move the flame around and you should see the signal change.
I put mine in a large vise to make sure I didn't burn anything.
Winford
Connect the signal wire to your voltmeter, should be an analog meter with at least 20K ohms/volt sensitivity. But in this case, you may be able to use a digital one.
The signal should be between 0.3 and 1.0 volts, after you get the tip( don't heat anything but the tip) red-hot with the torch. Move the flame around and you should see the signal change.
I put mine in a large vise to make sure I didn't burn anything.
Winford
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91 Explorer Check Engine Light
Winford,thanks for the information. I have looked at some other web sites that talk about O2 sensors and it appears that if the voltmeter is reading towards 0 volts it is indicating a lean condition and towards the 1 volt area a rich position. By increasing the temperature at the tip of the probe you should be simulating a lean(hot) condition with your voltmeter driving towards the 0 volt range.
Good information for the next time.
Thanks again
Dan
Good information for the next time.
Thanks again
Dan
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91 Explorer Check Engine Light
You are correct in the first part, the near 0 voltage does indicate a lean condition and the higher voltage indicates a rich condition - however in heating the tip with the torch, you do two things. First the O2 sensor must be hot to work, second the propane gas displaces oxygen around the tip, thereby making it "think" it is rich. Oxygen present means lean, oxygen deficiency means rich. If heating it up made it read 0, you couldn't use the test, because the voltage is always 0 under ambient conditions.
My first O2 sensor experience was with an new 84 (non-Ford) car. The dealer could not prevent it from surging (5 speed) because the O2 sensor kept giving it a too-high signal. After some intense research, I put an electronic 'trap' in the line clamping the top voltage to 0.6 V. It solved the problem.
Winford
My first O2 sensor experience was with an new 84 (non-Ford) car. The dealer could not prevent it from surging (5 speed) because the O2 sensor kept giving it a too-high signal. After some intense research, I put an electronic 'trap' in the line clamping the top voltage to 0.6 V. It solved the problem.
Winford
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