P2173: The engine computer has seen more airflow into the engine that the throttle position can't account for, which usually means air is leaking in somewhere

Throttle actuator control system: high airflow detected

Severity: Inspect soon

KBB advises against continuing to drive: expect poor throttle response, hesitation or limp mode. Get it diagnosed soon.

It gets more serious if:

Stop: Stop somewhere safe and have the car towed if the engine loses most of its power, stalls, won't respond to the pedal, or the transmission drops into neutral. That leaves you without drive in traffic.

P2173 in short

P2173 means the engine computer has detected a gradual rise in airflow that the throttle opening doesn't explain, usually from a vacuum leak. Chrysler calls it a vacuum leak detected. Vacuum leaks, crankcase vent tubes, throttle or sensor faults and software are common causes. Expect hesitation or limp mode; get it checked soon.

With an electronic throttle, the computer knows how much air should flow for a given throttle opening. When the manifold pressure or airflow reading shows more air than that, it concludes air is getting in elsewhere.

P2172 and P2173 are a pair: Ram's bulletin describes P2172 as a high airflow or vacuum leak detected with instantaneous accumulation, and P2173 as the slow-accumulation version. A sudden leak, like a hose popping off, tends to set P2172; a small, persistent leak sets P2173.

Both can come from a real leak or a sensor or software problem. Jeep fixed P2173 on the Renegade with a modified oil vapor tube, and several Chrysler bulletins correct it with a PCM reflash.

Most likely causes

Cause 1: Vacuum leak: cracked hose, loose intake boot or leaking gasket
Common general cause
Why it ranks here
KBB names vacuum leaks as the most common cause of both codes.
What would change this
Likelier with a hissing sound, a rough or high idle, or lean fuel-trim codes.
How to test the vacuum hoses and intake leaks
Cause 2: Crankcase vent (oil vapor) tube leak
Supported by vehicle data
Why it ranks here
Jeep's Renegade bulletin fixes P2173 with a modified oil vapor inlet tube.
What would change this
Likelier on a 2017-2018 Renegade or if a crankcase vent hose is cracked or disconnected.
How to test the crankcase ventilation (pcv) valve
Cause 3: Engine computer software (bulletin fix)
Supported by vehicle data
Why it ranks here
Chrysler, Dodge and Ram bulletins address P2172/P2173 with PCM software.
What would change this
Likelier on a covered model with no leak found.
How to test the engine control module (ecm / pcm)
Cause 4: Faulty MAP sensor or its circuit
Possible — needs testing
Why it ranks here
KBB lists a MAP malfunction for P2172, and Ram's bulletin lists MAP circuit codes with these codes.
What would change this
Likelier if P0107 or P0108 is stored too.
Cause 5: Throttle body, position sensors or wiring
Possible — needs testing
Why it ranks here
KBB lists the throttle body, throttle and pedal position sensors and wiring for P2173.
What would change this
Likelier if throttle position codes are stored too.
How to test the electronic throttle body
Cause 6: Abnormal system voltage
Possible — needs testing
Why it ranks here
KBB lists abnormal system voltage for both codes.
What would change this
Likelier with a weak battery, charging warning or other electrical codes.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

Step 1: Read all codes and check for bulletins covering your vehicle
Low riskTool: OBD-II scan tool
- IfA PCM software or vent tube bulletin covers your vehicle
  It meansHave the dealer apply it.
  Points to: Engine computer software (bulletin fix)
- IfP0107 or P0108 is also stored
  It meansCheck the MAP sensor circuit first.
  Points to: Faulty MAP sensor or its circuit
- IfLean or fuel-trim codes too
  It meansLook for a vacuum leak.
  Go to step 2
Step 2: Inspect the intake boot, vacuum hoses and crankcase vent tubes, then smoke-test the intake
Use cautionTool: Smoke machine
Warning:Work on a cool engine and keep clear of the fan and belts if the engine is running.
- IfCracked or disconnected vacuum hose or boot
  It meansRepair it.
  Points to: Vacuum leak: cracked hose, loose intake boot or leaking gasket
- IfLeak at a crankcase vent tube
  It meansReplace the tube.
  Points to: Crankcase vent (oil vapor) tube leak
- IfNo leak found
  It meansCheck the battery voltage and throttle.
  Go to step 3
Step 3: Check battery and charging voltage, then compare throttle position and MAP readings on the scan tool
Best left to a shopTool: Multimeter, scan tool
Warning:Keep clear of the fan and belts with the engine running, and don't short test leads across battery terminals.
- IfVoltage low or unstable
  It meansRepair the charging or battery fault.
  Points to: Abnormal system voltage
- IfThrottle position readings disagree or jump
  It meansDiagnose the throttle body and wiring.
  Points to: Throttle body, position sensors or wiring
- IfMAP reading implausible
  It meansReplace or repair the MAP sensor circuit.
  Points to: Faulty MAP sensor or its circuit

Symptoms

Check engine light
Poor throttle response or hesitation
Incorrect or rough idle
Limp mode
Stalling, loss of power or the transmission dropping into neutral Gets more serious: stop and have it checked.

Compare with: Check engine light with loss of power, Rough idle with the check engine light on

How to fix

Step 1: Ask a dealer to check your VIN for PCM software or vent tube bulletins; Chrysler, Dodge, Jeep and Ram have published fixes for P2173.
Step 2: Check that the air intake duct between the filter box and the throttle body is attached and not cracked.

Parts and cost context

Vacuum hoses and intake leaks:A cracked hose or intake boot is usually a cheap part; finding it is the main labour. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Ram

2019 · 1500
Supported by vehicle data
Bulletin covering P2172 and P2173 with MAP circuit codes. Whether the bulletin is still current is not verified.
2019–2021 · 1500
Supported by vehicle data
Transmission may go to neutral with P2172/P2173 and fuel-trim codes. Whether the bulletin is still current is not verified.

S1808000282Status unverified
MIL with P0107/P0108/P2172/P2173
20191500 · issued April 3, 2020 · NHTSA 10175652
Covers MIL with P0107, P0108, P2172 (high airflow/vacuum leak detected, instantaneous accumulation) and/or P2173 (high airflow/vacuum leak detected, slow accumulation).
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
S2118000013Status unverified
Transmission to neutral with P2172/P2173 and fuel-trim codes
2019–20211500 · issued August 5, 2021 · NHTSA 10218469
Transmission may go to neutral with P219A, P219B, P2173, P2172, P0172 and/or P0175 stored.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Jeep

2017–2018 · Renegade
Supported by vehicle data
Modified oil vapor inlet tube for P2173 with jerking or limp mode. Whether the bulletin is still current is not verified.
2008 · Patriot
Supported by vehicle data
PCM flash for P2173; also the Dodge Caliber. Whether the bulletin is still current is not verified.

09-010-20Status unverified
Modified oil vapor inlet tube for P2173
2017–2018renegade · issued July 2, 2020 · NHTSA 10178681
Loss of performance (jerking or limp mode) and/or MIL with P2173-00 "air leakage in manifold"; a modified oil vapor inlet tube is installed.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
18-019-08Status unverified
PCM flash for MIL with P2173
2008patriot, compass · issued April 25, 2008 · NHTSA 10024873
PCM reflash for a MIL with P2173. Also covers the Dodge Caliber.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Dodge

2013 · Dart
Supported by vehicle data
PCM flash addressing P2173 with other codes. Whether the bulletin is still current is not verified.

18-002-13Status unverified
PCM flash for P000B/P050B/P2173
2013dart · issued January 15, 2013 · NHTSA 10189375
PCM reflash addressing P000B, P050B and P2173.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

All Electronic throttle and accelerator pedal codes

Sources and review

P2173 Throttle Actuator Control System - High Air Flow Detected — Kelley Blue Book
Ram S1808000282: P0107/P0108/P2172/P2173 (Ram 1500) — FCA US / NHTSA , April 3, 2020
Ram S2118000013: transmission shifts to neutral with P219A/P219B/P2172/P2173/P0172/P0175 (Ram 1500) — FCA US / NHTSA , August 5, 2021
FCA 09-010-20: modified oil vapor inlet tube for P2173-00 air leakage in manifold (Renegade) — FCA US / NHTSA , July 2, 2020
P2172 Throttle Actuator Control System - Sudden High Air Flow Detected — Kelley Blue Book
Chrysler 18-019-08: PCM flash for MIL with P2173 (Patriot, Compass, Caliber) — Chrysler LLC / NHTSA , April 25, 2008
Chrysler 18-002-13: PCM flash for P000B/P050B/P2173 (Dart) — Chrysler Group / NHTSA , January 15, 2013

Last reviewed: October 15, 2026
Written by: Saurabh K.
Editorial review: Pending
Technician review: Technician review pending

This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

Severity: Inspect soon

Most likely causes

Cause 1: Vacuum leak: cracked hose, loose intake boot or leaking gasket

Cause 2: Crankcase vent (oil vapor) tube leak

Cause 3: Engine computer software (bulletin fix)

Cause 4: Faulty MAP sensor or its circuit

Cause 5: Throttle body, position sensors or wiring

Cause 6: Abnormal system voltage

What to test first

Step 1: Read all codes and check for bulletins covering your vehicle

Step 2: Inspect the intake boot, vacuum hoses and crankcase vent tubes, then smoke-test the intake

Step 3: Check battery and charging voltage, then compare throttle position and MAP readings on the scan tool

Symptoms

How to fix

Parts and cost context

On your vehicle

RamYour car

JeepYour car

DodgeYour car

Related codes

Sources and review

Ram

Jeep

Dodge