Throttle Position Sensor - Sensor 1 Failure
The throttle position sensor is not sending a valid signal to the ECM.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The throttle position sensor (TPS) tells the engine control module (ECM) how far the throttle is open. If it’s failing, the ECM doesn’t know how much air to mix with fuel, which can cause poor performance or stalling.
What the computer is actually seeing
The ECM expects the TPS to send a voltage signal that varies between 0.5V (idle) and about 4.5V (full throttle) in response to accelerator pedal input. If it sees a constant signal or no signal at all, it sets SPN 3582.
What a healthy reading looks like
Idle should read around 0.5V, and at full throttle, it should be close to 4.5V. The change should be smooth and progressive between those values.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring and connector on the TPS for corrosion or looseness. If damaged, repair or replace.
- 22. Measure the voltage at the TPS connector while moving the throttle. Look for a smooth change from 0.5V to 4.5V. If not within this range, replace the TPS.
- 33. If the TPS is fine, check for voltage on the signal wire with the key on. You should see around 5V reference voltage. If not, check the wiring back to the ECM.
- 44. If wiring is okay, check the ECM for faults. You may need to consult the vehicle’s service manual for testing procedures.
Common causes
- Wiring issues (shorts or opens) in TPS circuit
- Faulty throttle position sensor
- Corrosion or bad connection in the sensor plug
- ECM malfunction
- Mechanical issues with the throttle body
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
It's best not to drive extensively. You may experience poor acceleration and unexpected stalls.
Will this code come back after I clear it?
If the underlying issue isn't fixed, yes, it will likely return.
Why does this code pair with other throttle-related codes?
Throttle sensor issues often show related codes due to shared wiring or component dependencies.
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