1995 ford taurus check engine light code 159

[handyandyap]

My 1995 taurus check engine light came on. I had the codes checked and found codes 159 mass air flow sensor (MAF) out of range, 158 sig too high and 157 sig too low. I replaced the MAF and the check engine light continued. The cars performance did not change. The car runs good except, at times, when the check engine light is off it hesitates or sometimes cuts out. This does not happen often, just enough to give me that uneasy feeling. I changed the O2 sensor located close to the cat converter. I don't know if this car has more than one. If it does, please someone tell me where it's located and I will replace it. Anyway, I have replaced the O2 sensor and the taurus seems to be running better, but it did cut out real good on the way home today. And the check engine light continues. Please, I need some advice. Thank you for reading this!

[~manuel~]

Originally Posted by handyandyap

My 1995 taurus check engine light came on. I had the codes checked and found codes 159 mass air flow sensor (MAF) out of range, 158 sig too high and 157 sig too low. I replaced the MAF and the check engine light continued. The cars performance did not change. The car runs good except, at times, when the check engine light is off it hesitates or sometimes cuts out. This does not happen often, just enough to give me that uneasy feeling. I changed the O2 sensor located close to the cat converter. I don't know if this car has more than one. If it does, please someone tell me where it's located and I will replace it. Anyway, I have replaced the O2 sensor and the taurus seems to be running better, but it did cut out real good on the way home today. And the check engine light continues. Please, I need some advice. Thank you for reading this!

when you say cut out do you mean it is dying on you while you are driving? also did you have that problem prior to the check engine light coming on with those MAF codes? or did it start at the same time you started getting that CEL ? there are two O2 sensors. one on each exhaust manifold,before the cats.although i have never seen an O2 sensor cause an engine to die in flight.

[Madman762]

A diagnostic code could just as easily be caused by a bad connection. If the wires leading to the MAF sensor are not properly connected, it may give the computer a false signal. Its always a good idea to check the wiring of any sensor or other electrical part that a diagnostic code points to before replacing the part arbitrarily.

[Madman762]

Silly question, but after replacing the MAF sensor, did you follow whatever procedure is neccessary to clear the codes from the computer??

[handyandyap]

Originally Posted by ~manuel~

when you say cut out do you mean it is dying on you while you are driving? also did you have that problem prior to the check engine light coming on with those MAF codes? or did it start at the same time you started getting that CEL ? there are two O2 sensors. one on each exhaust manifold,before the cats.although i have never seen an O2 sensor cause an engine to die in flight.

Thank you very much for your reply! When I say "cut-out", it's more like a hesitation or a stumble or like a misfire or a lack of fuel for a second. This only started after the check engine light came on. The cars performance did not change after I changed the MAF sensor. This hesitation seemed to get better after I changed the O2 sensor, but the last time I drove the car it did this "cut-out" the worse. This only happens during acceleration and only when the check engine light is off. I have not noticed any performance issues with the check engine light on. Also, have not and I do not know how to clear the codes. Is there a simple way to clear the codes and would this help?

[handyandyap]

Originally Posted by Madman762

Silly question, but after replacing the MAF sensor, did you follow whatever procedure is neccessary to clear the codes from the computer??

Thank you very much for your reply! When I say "cut-out", it's more like a hesitation or a stumble or like a misfire or a lack of fuel for a second. This only started after the check engine light came on. The cars performance did not change after I changed the MAF sensor. This hesitation seemed to get better after I changed the O2 sensor, but the last time I drove the car it did this "cut-out" the worse. This only happens during acceleration and only when the check engine light is off. I have not noticed any performance issues with the check engine light on. Also, have not and I do not know how to clear the codes. Is there a simple way to clear the codes and would this help?

[Madman762]

On most 1995 and earlier cars, you can clear the codes by disconnecting the battery for a few seconds. Step on the brake pedal a couple of times to drain any residual energy in the system.

[~manuel~]

Originally Posted by handyandyap

My 1995 taurus check engine light came on. I had the codes checked and found codes 159 mass air flow sensor (MAF) out of range, 158 sig too high and 157 sig too low. I replaced the MAF and the check engine light continued. The cars performance did not change. The car runs good except, at times, when the check engine light is off it hesitates or sometimes cuts out. This does not happen often, just enough to give me that uneasy feeling. I changed the O2 sensor located close to the cat converter. I don't know if this car has more than one. If it does, please someone tell me where it's located and I will replace it. Anyway, I have replaced the O2 sensor and the taurus seems to be running better, but it did cut out real good on the way home today. And the check engine light continues. Please, I need some advice. Thank you for reading this!

have you checked what your fuel presure readings are? Also those MAF codes lead me to believe that there may be a short somewhere in the circuit or a possible bad pcm. the normal range for a MAF is 0-5 volts. something is causing the signal to be to high or to low, and you have replaced the MAF so you can rule that out. trace the wires and see if you can find if it rubbed through somewhere.

[handyandyap]

Originally Posted by ~manuel~

have you checked what your fuel presure readings are? Also those MAF codes lead me to believe that there may be a short somewhere in the circuit or a possible bad pcm. the normal range for a MAF is 0-5 volts. something is causing the signal to be to high or to low, and you have replaced the MAF so you can rule that out. trace the wires and see if you can find if it rubbed through somewhere.

Thank you, I will look for a short. What is a "pcm" and can one be replaced?

[handyandyap]

Does anyone have any suggestions?