P1120
ToyotaThrottle position sensor out of range
Medium SeverityYour throttle position sensor ain't reading right. That means the computer don't know where your gas pedal is, messing with how the engine runs.
⚠️ Before You Begin (Safety First)
Don't ignore this. If the throttle gets stuck open or closed, you're in trouble. Pull over safely if the engine acts up, and turn it off.
Common Symptoms
- Check Engine light is on
- Rough idle
- Engine stalls
- Poor acceleration
- Vehicle surges or jerks
- Hard starting
Common Causes
- Bad throttle position sensor
- Frayed or broken wiring to the sensor
- Corroded electrical connector
- Loose TPS connection
- Rarely, a faulty engine computer (ECM)
Frequently reported on: Toyota Camry 1998-2002, Toyota Tacoma 1995-2004, Toyota 4Runner 1996-2002, Toyota Corolla 1998-2002, Toyota Sienna 1998-2003
Diagnostic Steps
- Hook up a scanner, verify the P1120 code.
- Check the wiring and connector at the throttle position sensor for damage or corrosion. Make sure it's snug.
- Use a multimeter to test the TPS voltage output while moving the throttle by hand. It should increase smoothly without drops.
- If the TPS readings are jumpy or outside spec, replace the throttle position sensor. It's usually a couple of bolts.
- Clear the code with your scanner and take it for a test drive to see if it comes back.
👨🔧 When to Call a Professional
If you swap the throttle position sensor and the code comes right back, or if the idle's still crazy, get it to a shop. Could be wiring or the computer itself.
Commonly Asked Questions
What does P1120 mean on my Toyota?
It means the computer sees a problem with the throttle position sensor signal. It's either out of range or acting funny.
Can I drive with a P1120 code?
You can, but it's not smart. Your engine might run rough or even stall. Get it fixed.
How do I test the throttle position sensor?
Use a multimeter on the sensor wires. Check for a steady voltage change as you open and close the throttle by hand. Any spikes or drops mean it's bad.
Is the TPS hard to replace?
Nah, usually just two screws and a plug. Pretty easy job if you've got basic tools.
Will cleaning the throttle body fix P1120?
Not usually for this code. This is a sensor signal problem, not a dirty throttle plate. You need to check the sensor itself or its wiring.