P1120 CE code

[holmes4567]

I am receiving a P1120 CE code, I have a low idle and one day when it as about 5 degrees out side the truck almost did not start. I got the code for the first time on Saturday, I disconnected the battery and the code went off until Sunday night. I took it to auto zone today and the retrieved the code for me. They kept telling me it was a fuel pressure regulator. I did some searching and it seems like people are saying its the TPS, MAF, spark plug/wires, or fuel pressure regulator. I just recently put some SeaFoam in the tank and my dad (without telling me) then up in some Lucas cleaner (not sure the exact name) in the same tank of gas. could this be causing the CEL? I am trying to sell the car because I lost my job, and don't want to spend a bunch of money on it. any help would be great!

thanks in advance!!
Dave

 

[holmes4567]

Sorry I forgot to add its a 4.0 SOHC with 172k

 

[Cobraguy]

Double check you are giving us the correct code. A P1120 is for the TPS. (I beleive it's telling you it's low IIRC) If that is correct, check the voltage of your Throttle Position Sensor at idle and at WOT and make sure it's in spec. Also, check the voltage while doing a complete sweep of the sensor. Do it slowly. The voltage should rise and fall with the throttle very smoothly with no jumps or hesitation. Replace of necessary. If the bolts holding the TPS are stuck (seized), use a small propane torch...such as a soldering torch...to put some heat into them first and break the bond of the thread locker.

 

[aldive]

P1120 is for a TPS out of range.

 

[Cobraguy]

Isn't that what I said?