P2101: Throttle Actuator A Control Motor Circuit Range/Performance

Here the controller compares where throttle A should be with where its position sensors say it is. GM's 2018 table 18OBDG03A flags a gap of more than 10 percent between measured and modelled position after 15 counts at 12.5 ms each, classed by GM as Type A with immediate MIL; the 2006/2007 tables used 8.4 percent. VW's 2014 data book accepts 4-50 percent deviation or a drive duty cycle above 80 percent. Ford sets it with MIL and wrench lamp; Mercedes-AMG M177 engines show it with corroded throttle connector pins, and GM issued field bulletins for the LGZ V6 and 2017 V8 trucks. Causes are mostly mechanical or contact problems, not a dead circuit (P2100). Expect reduced power or limp mode.

High severity. Can I keep driving?Avoid continuing to drive: the car may go into limp mode and suddenly lose power, which is dangerous when passing or merging. If this happens, get off the road as soon as you safely can and take the car to a repair shop.

Symptoms

Reduced engine power message or limp mode
Engine warning lamp on
Hesitation or uneven idle
Stalling in some cases

Most likely causes

Carbon or ice makes the throttle plate stiff or sticky
High resistance at the throttle connector pins
Worn gear train or weak motor inside the throttle body
Deformed inlet duct or leak at the throttle body

What to check, in order

Start with the simplest. You can tick off each step.

Check the pedal and throttle connectors
Compare the reading with other engine data while varying the engine speed.
Use live data to confirm that both sensors rise smoothly and consistently
Clean the throttle if it has carbon buildup
Run the relearn procedure with the scanner if the manufacturer requires it
Replace the part identified by the diagnosis

Good to know

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P2101 means

P: Powertrain: engine and transmission
2: Generic code: same on every make
1: Air and fuel
01: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2101?

Avoid continuing to drive: the car may go into limp mode and suddenly lose power, which is dangerous when passing or merging. If this happens, get off the road as soon as you safely can and take the car to a repair shop.

What causes code P2101?

The most common causes are: carbon or ice makes the throttle plate stiff or sticky; high resistance at the throttle connector pins; worn gear train or weak motor inside the throttle body.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.