I pulled the codes to try and figure out why my car is acting terrible and i got 121,116,157,172,173,136,137,536,632,158,312,581,564 I found what they all mean and i know what they do and affect but im not sure of a couple. 116- ECT out of self test range 0.3 to 3.7 volts? 157- MAF sensor went below 0.4 volts during the last 80 warm-up cycles? 158- MAF sensor went above 4.5 volts during the last 80 warm-up cycles? btw my Tps sensor is out so i know i need to replace it. Should i then just clean the MAF with MAF Cleaner and Q-tips? If you have any ideas please let me know. thanks
94 Mustang Gt 5.0 ECT problem??
- Thread starter MarshallPhil3
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Canary94GT
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holy smokes that's a lot of codes
116 can occur if you ran the self test with the engine cold, so if u did dont worry about it
116 can occur if you ran the self test with the engine cold, so if u did dont worry about it
You need to understand what these sensors do and how they operate in a computer controlled environment. Let's just deal with the MAF in really simple terms. The computer applies voltage to the MAF sensor such that the sensor maintains an constant temperature of 200*F. As the air flow increases the temperature starts to fall and the computer calculates the mass of air based on the increased volts needed to keep the sensor at 200*. This calculated air mass is then used to calculate the extra fuel needed for the air mass to maintain the target AFR at that particular engine load. The O2 sensors provide feedback to the computer to confirm and further adjust the fuel requirements. All the sensors are constantly being monitored with the outputs being used to adjust and optimize fuel and emission requirements. You simply cannot take out a sensor and expect the engine to run well. In your case you know the MAF sensor has been disconnected but you don't know whether all or some of the other codes are a result of not using the MAF. I would clear all the codes, install a known good MAF, do a full ignition tune up (plugs, wires, cap, rotor, air and fuel filters, etc) to give you a workable baseline. To do otherwise is just a waste of time.