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P1120.... P1221

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Old Aug 23, 2009 | 08:44 PM
  #1  
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Default P1120.... P1221

ok so upon driving thru a terrible band of rain thru the remains of hurricane Bill, the street that i was on was completely flooded. i drove as slow as possible but had no where to go but thru it...about 3 or 4 min later when i tried to give it a bit more throttle to get up the hill i live on i instantly got check engine light and the reduce engine power on the DIC. what did i do to my car??...will it be ok if it dries out tomorrow?.... the codes that i pulled were P1120 and P1221...

I also got a traction control code...but cant remember it...i will post it tomorrow.....

please help.....thankyou....Don
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Old Aug 23, 2009 | 09:21 PM
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good luck
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Old Aug 23, 2009 | 10:33 PM
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are you serious?.........
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Old Aug 23, 2009 | 10:40 PM
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Pull you airfilter and see if the housing has water in it and if the filter is saturated.Hopefully you did not inhale water into your engine in sufficient amounts to hydro lock it.
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Old Aug 23, 2009 | 10:45 PM
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oh my word....i was trapped....there was no where to go....i mean it got me the 2 miles home....is this something insurance can cover?....i do have full coverage....

how do i know how long to let the housing dry out?....crap im skrewed....
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Old Aug 23, 2009 | 10:59 PM
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ok i pulled the air cleaner and it was bone dry...this happened about 3-4 hours ago...but im still pulling the same codes.....whats next?...

the traction control code was c1278

Last edited by DonsC5; Aug 23, 2009 at 11:00 PM. Reason: wrong code
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Old Aug 23, 2009 | 11:10 PM
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P1120 - TP Sensor 1 Circuit

P1221 - TP Sensors 1, 2 Performance

DTC P1221
Circuit Description
The throttle position (TP) sensor is mounted on the throttle body assembly. The sensor is actually 2 individual TP sensors within 1 housing. Two separate signal, low reference and 5 volt reference circuits are used in order to connect the TP sensor assembly to the throttle actuator control (TAC) module. The 2 sensors have opposite functionality. The TP sensor 1 signal voltage is pulled up to the reference voltage as the throttle opens, from below 1 volt at closed throttle to above 3.5 volts at wide open throttle (WOT). The TP sensor 2 signal voltage is pulled down to the low reference from around 3.8 volts at closed throttle to below 1 volt at WOT. TP sensor 1 and APP sensor 1 share a 5-volt reference circuit that is connected within the TAC module. TP sensor 2 and APP sensor 2 share a 5-volt reference circuit that is connected within the TAC module. If an out of range condition is detected with the TP sensors, this DTC will set and the Reduced Engine Power message will be displayed.

Conditions for Running the DTC
DTCs P1517, or P1518 are not set.
The ignition switch is in the crank or run position.
The ignition voltage is greater than 5.23 volts.
Conditions for Setting the DTC
TP sensor 2 disagrees with TP sensor 1 by more than 7.5 percent.
All above conditions are present for less than 1 second.
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
The control module commands the TAC system to operate in the Reduced Engine Power mode.
A message center or an indicator displays Reduced Engine Power.
Under certain conditions the control module commands the engine OFF.
Conditions for Clearing the MIL/DTC
The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.
Diagnostic Aids
Inspect the TAC module connectors for signs of water intrusion. When water intrusion occurs, multiple DTCs could be set with no DTC circuit or component conditions found during diagnostic testing.
When the TAC module detects a condition within the TAC system, more than 1 TAC system related DTC may set. This is due to the many redundant tests that run continuously on this system. Locating and repairing 1 individual condition may correct more than 1 DTC. Disconnecting components during testing may set additional DTCs. Keep this in mind when reviewing the stored information, Capture info.
If this DTC is determined to be intermittent, refer to Intermittent Conditions .

DTC P1120
Circuit Description
The throttle position (TP) sensor is mounted on the throttle body assembly. The sensor is actually 2 individual TP sensors within 1 housing. Two separate signal circuits, low reference circuits and 5-volt reference circuits are used in order to connect the TP sensor assembly to the throttle actuator control (TAC) module. The 2 sensors have opposite functionality. The TP sensor 1 signal voltage is pulled up to the reference voltage as the throttle opens, from below 1 volt at closed throttle to above 3.5 volts at wide open throttle (WOT). The TP sensor 2 signal voltage is pulled down to low reference from around 3.8 volts at closed throttle to below 1 volt at WOT. TP sensor 1 and APP sensor 1 share a 5-volt reference circuit that is connected within the TAC module. TP sensor 2 and APP sensor 2 share a 5-volt reference circuit that is connected within the TAC module. If an out of range condition is detected with the TP sensor 1, this DTC will set and the Reduced Engine Power message will be displayed.

Conditions for Running the DTC
DTCs P1517, or P1518 are not set.
The ignition switch is in the crank or in the run position.
The ignition voltage greater than 5.23 volts.
Conditions for Setting the DTC
TP sensor 1 signal voltage is less than 0.13 volts or greater than 4.87 volts.
All of the above conditions present for less than 1 second.
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
The control module commands the TAC system to operate in the Reduced Engine Power mode.
A message center or an indicator displays Reduced Engine Power.
Under certain conditions the control module commands the engine OFF.
Conditions for Clearing the MIL/DTC
The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.
Diagnostic Aids
Inspect the TAC module connectors for signs of water intrusion. When water intrusion occurs, multiple DTCs could be set with no DTC circuit or component conditions found during diagnostic testing.
When the TAC module detects a condition within the TAC system, more than one TAC system related DTC may set. This is due to the many redundant tests that run continuously on this system. Locating and repairing 1 individual condition may correct more than 1 DTC. Disconnecting the components during testing may set additional DTCs. Keep this in mind when reviewing the stored information, Capture info.
If this DTC is determined to be intermittent, refer to Intermittent Conditions .
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Old Aug 23, 2009 | 11:20 PM
  #8  
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Sounds like your Throttle Position(TP) Sensor

Here's a picture of it getting unplugged.

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Old Aug 24, 2009 | 01:44 PM
  #9  
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I had a TP sensor screwing up on me from my engine ingesting water and I could unplug it with the engine off and blow it out and replug it sometimes to get it to work. After a month or so I did have to replace it though. Might try that to see if it got moisture in the plug. If you have one of the anti-tamper torx style screwdriver bits you could pull it off and try blowing it out to get any moisture out of it. They are not sealed very well on the throttle body side so if moisture made its way into the throttle body it is possible it could have gotten inside it. I did pry mine apart and found moisture in it. Luckily they are not too expensive if your quits.
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Old Aug 24, 2009 | 04:54 PM
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From: Portland Maine
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thankyou Blown427conv....i pulled the throttle control sensor and disconnected the wiring and sure enough?..one of the leeds had blueish green corrosion on it....i cleaned it out, plugged it in and like magic it was new again....i cant speak enough about the level of information and helpfulness this forum provides.....thank you all...happy driving!!!

Don
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