Ok i pulled codes and got code 23. The car was at the shop bc i had prolems installing my LTs and they said they fixed everything and its still running a bit to rich. The other code i pulled was for the ego was reading lean i forget the exact code number. Well the TPS was replaced and is still throwing the code. I talked to a ford dealer today and they said when you replacv the TPS you have to bring the car in to a ford dealership and have the computer reprogrammed to learn the new TPS. My computer was also replace due to me shocking my system. He said it costs about 45$ to reprogram. I have never heard anyone mention this before i think he was just trying to get money out of me. Can anyone help me out.
Pulled codes and error with TPS HELP!!
- Thread starter xexitenglishx
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Disconnect the battery for 20 minutes, and then reconnect it. Then drive the car ar a steady speed over 45 MPH for 15 minutes. You have just re-programmed the computer for the new TPS & new TPS setting.
Well all you got to do is check voltage between the green & black wire & adjust to .98 or .99 you'll notice the idle change a bit but I noticed nothing when it came to air fuel ratio as I am having a lean issue myself right now I'm trying to troubleshoot, did you try adjusting the fuel pressure regulator ?
the specific codes dont necessarily mean to replace that part. can you be more specific on what the other codes were?
the puter will trim the A/F ratio - if you up the Fuel Pressure, the puter will shorten the pulsewidth of the injectors, to compensate (as it learns), so it can remain stoich.
if you have an O2 saying you are lean, the puter will try to fatten the mixture - causing an artificially rich condition.
that is where im going with knowing what the other codes are.
good luck.
the puter will trim the A/F ratio - if you up the Fuel Pressure, the puter will shorten the pulsewidth of the injectors, to compensate (as it learns), so it can remain stoich.
if you have an O2 saying you are lean, the puter will try to fatten the mixture - causing an artificially rich condition.
that is where im going with knowing what the other codes are.
good luck.
actually, JR is the man you should talk to. he has a nice test for checking the lambda's, if you are interested (if you dont want to blindly swap some new ones in). one has to be careful, as it is easy to blow the circuit (the circuit switches from 0 to 1 volt, supplying its own voltage). there are a few things one must be careful of when testing them out - JR's post sums it up quite nicely. 
Code 41 or 91 - O2 indicates system lean. Look for a vacuum leak or failing O2 sensor.
The computer sees a lean mixture signal coming from the O2 sensors and tries to compensate by adding more fuel.
The following is a Quote from Charles O. Probst, Ford fuel Injection & Electronic Engine control:
"When the mixture is lean, the exhaust gas has oxygen, about the same amount as the ambient air. So the sensor will generate less than 400 Millivolts. Remember lean = less voltage.
When the mixture is rich, there's less oxygen in the exhaust than in the ambient air , so voltage is generated between the two sides of the tip. The voltage is greater than 600 millivolts. Remember rich = more voltage.
Here's a tip: the newer the sensor, the more the voltage changes, swinging from as low as 0.1 volt to as much as 0.9 volt. As an oxygen sensor ages, the voltage changes get smaller and slower - the voltage change lags behind the change in exhaust gas oxygen.
Because the oxygen sensor generates its own voltage, never apply voltage and never measure resistance of the sensor circuit. To measure voltage signals, use an analog voltmeter with a high input impedance, at least 10 megohms. Remember, a digital voltmeter will average a changing voltage." End Quote
Measuring the O2 sensor voltage at the computer will give you a good idea of how well they are working. The computer pins are 29 (LH O2 with a dark green/pink wire) and 43 (RH O2 with a dark blue/pink wire). Use the ground next to the computer to ground the voltmeter.
The O2 sensor ground is in the wiring harness for the fuel injection wiring. I grounded mine to one of the intake manifold bolts
The computer sees a lean mixture signal coming from the O2 sensors and tries to compensate by adding more fuel.
The following is a Quote from Charles O. Probst, Ford fuel Injection & Electronic Engine control:
"When the mixture is lean, the exhaust gas has oxygen, about the same amount as the ambient air. So the sensor will generate less than 400 Millivolts. Remember lean = less voltage.
When the mixture is rich, there's less oxygen in the exhaust than in the ambient air , so voltage is generated between the two sides of the tip. The voltage is greater than 600 millivolts. Remember rich = more voltage.
Here's a tip: the newer the sensor, the more the voltage changes, swinging from as low as 0.1 volt to as much as 0.9 volt. As an oxygen sensor ages, the voltage changes get smaller and slower - the voltage change lags behind the change in exhaust gas oxygen.
Because the oxygen sensor generates its own voltage, never apply voltage and never measure resistance of the sensor circuit. To measure voltage signals, use an analog voltmeter with a high input impedance, at least 10 megohms. Remember, a digital voltmeter will average a changing voltage." End Quote
Measuring the O2 sensor voltage at the computer will give you a good idea of how well they are working. The computer pins are 29 (LH O2 with a dark green/pink wire) and 43 (RH O2 with a dark blue/pink wire). Use the ground next to the computer to ground the voltmeter.
The O2 sensor ground is in the wiring harness for the fuel injection wiring. I grounded mine to one of the intake manifold bolts
