P2038 OBD-II Trouble Code: Reductant Inj Air Press Sensor Circ Range/Performance

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P2038 code

P2038 is a diagnostic trouble code (DTC) for "Reductant Inj Air Press Sensor Circ Range/Performance". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$20.00
Toyota$20.00
BMW$20.00
SCHEDULE P2038 DIAGNOSTIC Get a fair and transparent estimate upfront

The P2038 code is a general OBD-II diagnostic trouble code that points to a fault with the reductant injection air pressure sensor “A” circuit range / performance.

What the P2038 code means

The reductant injection system adds air or fluid to the exhaust system to aid in the burning of emissions gasses. The air pressure sensor is used to monitor the pressure of the exhaust.

When out of range sensor performance is detected the P2038 code is set. This causes the Check Engine Light to be displayed on the dashboard and a failsafe mode enabled. The failsafe mode is used to protect the vehicle from further damage and will remain in effect until the sensor falls within range or the fault is resolved.

What causes the P2038 code?

The most likely causes of the P2038 code are:

  • An open or short in the wiring harness
  • Exhaust pressure sensor failure
  • Exhaust leak
  • Poor electrical connection

What are the symptoms of the P2038 code?

In most cases, the P2038 code will not have any symptoms other than the Check Engine Light on the dashboard. The vehicle may suffer a lower than normal fuel mileage and the exhaust emissions may be higher.

How does a mechanic diagnose the P2038 code?

A mechanic will begin by hooking up a scan tool and checking for any codes stored in the ECU. Any codes found, as well as their associated freeze frame data, will be noted. All codes will be cleared and a road test will be performed under similar conditions as the freeze frame data.

A visual inspection will be done looking for any obviously damaged or broken components. Next, the scan tool will be used to check the EGT sensor readings and the exhaust gas pressure readings. Once the exhaust gas temperature is checked, a multimeter will be used to check for the proper voltage at the pressure sensor. Finally, the exhaust system will be checked for any leaks present.

Common mistakes when diagnosing the P2038 code

The most common mistake is overlooking an exhaust leak as the cause of P2038, and looking at more extensive issues. Step-by-step diagnosis is key to accurately fixing the P2038 code.

How serious is the P2038 code?

The P2038 code will not prevent the vehicle from being driven in any way once the code is triggered. With any code this should be repaired as soon as possible for normal vehicle operation.

What repairs can fix the P2038 code?

Common repairs for the P2038 code are:

Additional comments for consideration regarding the P2038 code

Looking for an exhaust leak can be easy if the right steps are taken. The first way is to check for any black sooty stains on the exhaust. This is a clear indication of unburned fuel particles exiting the exhaust in the form of a leak. Another way to check is placing your hand close to the exhaust to feel for any air exiting the exhaust while the engine is running. Caution should be taken when performing this method as the exhaust is very hot and will easily burn your hands.

Need help with a P2038 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230

P2038
trouble codes
Check Engine Light

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P2038 code.

SCHEDULE P2038 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.8/5

Number of Reviews

5,170

Rating Summary
4,765
197
50
27
131
4,765
197
50
27
131

Fred

16 years of experience
364 reviews
Fred
16 years of experience
Mercedes-Benz E500 - Check Engine Light is on - Conroe, Texas
Fred was very friendly and thorough to get to the root of the issue. Even when he could not find a fault to why my engine light was on, he went above and beyond to make absolutely sure that the concern was minimized. Turns out, all that needed to be done was a reset but his diagnostic to address my issues was very intricate and appreciated.

David

17 years of experience
37 reviews
David
17 years of experience
Chevrolet Cruze - Check Engine Light is on - Aurora, Colorado
David was on time, professionalisms & honest! I would definitely request him again and pass along to friends/family.

John

18 years of experience
18 reviews
John
18 years of experience
Dodge Ram 1500 - Check Engine Light is on - Memphis, Tennessee
Demonstrated good integrity. Advised me when work I thought needed done was unnecessary and was helpful in identifying issues that needed to be addressed

Robert

21 years of experience
17 reviews
Robert
21 years of experience
Chrysler 200 - Check Engine Light is on - Fort Worth, Texas
Robert did a good job working on my car and letting me know what's needed to keep my car driving smoothly.


More related articles

P0358 OBD-II Trouble Code: Ignition Coil H Primary/Secondary Circuit Malfunction
Trouble code P0358 means the powertrain control module (PCM) has failed to receive a valid pulse signal from ignition coil H
P2344 OBD-II Trouble Code: Cylinder #9 Above Knock Threshold
P2344 means an issue with the cylinder 9 knock sensor circuit. Some causes are faulty knock sensor, damaged wires, and cylinder firing malfunctions.
P0524 OBD-II Trouble Code: Engine Oil Pressure Too Low
P0524 means there is an abnormally low oil pressure reading often due to defective engine components or incorrect oil viscosity.

Related questions

Check engine and ABS light came on then went away

Hello, thank you for writing in. Battery issues cause malfunctions with all of the systems that use its power to function. Most commonly, the charging system light, check engine light, and ABS light come on when there is an issue...

Check engine check battery leaking smoke

If it was leaking "antifreeze" or "coolant" on the freeway, that signifies a cooling system leak although it is also possible that your car is overheating (due to a cooling system problem like a stuck thermostat or an engine issue)...

P2107 - 2005 Ford Freestyle

Hello. P2107 is the code for an issue with the vehicle's throttle control module processor. Basically, the computer has detected an issue with the vehicle's electronic throttle body and has put the vehicle in safe mode. The throttle body...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com