P1100 OBD-II Trouble Code: Mass Airflow Sensor Intermittent

Our certified mechanics come to you · 12-month, 12,000-mile warranty

SCHEDULE P1100 DIAGNOSTIC Get a fair and transparent estimate upfront
Red-stars EXCELLENT RATING ON

Cost of diagnosing the P1100 code

P1100 is a diagnostic trouble code (DTC) for "Mass Airflow Sensor Intermittent". 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 for $70.00. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $30.00 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$70.00$30.00
Toyota$70.00$30.00
BMW$70.00$30.00
SCHEDULE P1100 DIAGNOSTIC Get a fair and transparent estimate upfront

diagnostic check engine light

P1100 code definition

A P1100 trouble code is stored when the Powertrain Control Module (PCM) detects a Mass Air Flow (MAF) sensor signal that falls above or below the manufacturer calibrated limits. Some other, related trouble codes that might appear alongside a P1100 trouble code include a P1101, P1102, P1103, and P1104 code.

What the P1100 code means

The MAF sensor measures the volume and density of the air entering the engine. This data is used by the PCM to calculate the correct fuel to air mixture so that the engine can operate efficiently while in operation. When the PCM detects a variance in the voltage from the MAF sensor that falls outside of manufacturer's specifications, a P1100 trouble code is stored and the Check Engine light illuminates.

What causes the P1100 code?

Some causes of a P1100 trouble code include a dirty or faulty MAF sensor, a dirty MAF sensor wire. An air leak before or after the MAF sensor can also cause the storage of this code. A short in the MAF sensor harness can also cause a P01100 trouble code.

What are the symptoms of the P1100 code?

Some common symptoms of a P1100 trouble code include trouble stahiccupping vehicle, vehicle stalling, hesitation under load, rough idling, and hiccuping by the engine. In addition, the vehicle can suffer from reduced fuel efficiency.

How does a mechanic diagnose the P1100 code?

To diagnose a P1100 trouble code, a mechanic needs to have an advanced scanner, an oscilloscope, and a digital volt/ohm meter. In addition, they should perform the following steps:

  • Check all of the wiring, connectors, and components associated with the MAF sensor for damage or fault.
  • After replacing all faulty or damaged items, the mechanic should clear the P1100 trouble code and test the system to see if the code returns.
  • If the code returns, the mechanic should next test the MAF sensor using the digital volt/ohm meter, looking for voltage and a ground signal.
  • If neither is detected, the mechanic should disconnect the PCM and related control modules and check the continuity of the MAF sensor with the battery ground, comparing their findings with the manufacturer's specifications.
  • The mechanic might also need to perform a smoke test of the vacuum system to see if there is a leak either after or before the sensor.
  • Another way for a mechanic to check the MAF sensor output is by using an oscilloscope attached to an injector ground terminal to test injector timing. Overlong injector timing can signal that the fuel mixture is either too rich or too lean, a condition usually caused by a faulty MAF sensor.
  • Finally, the mechanic should clear the code again and retest the system to see if it returns.

Common mistakes when diagnosing the P1100 code

Mechanics often make the mistake when diagnosing a P1100 trouble code of replacing the MAF sensor without first checking if there is faulty or damaged wiring within the MAF sensor wiring harness. The result is that the problem remains unfixed and the code returns.

How serious is the P1100 code?

While a P1100 trouble code may not prevent a vehicle from operating, drivers can expect a reduction in the fuel efficiency of the vehicle in situations where the engine is running too rich. It is best to get a P1100 trouble code diagnosed and fixed as soon as possible to avoid the stalling and hard start conditions that often accompany the code storage.

What repairs can fix the P1100 code?

To repair a P1100 trouble code, the mechanic needs to perform the following:

  • Replace any faulty wiring, connectors, or components within the MAF sensor wiring harness.
  • Before replacing the MAF sensor, the mechanic should carefully remove the sensor and clean it using cleaner specially made for cleaning the MAF sensor.
  • Once the sensor is clean completely dry, the mechanic should replace it, clear the code, and test the system to see if the code returns.
  • If the sensor is still not working properly, it should be replaced with a new MAF sensor.
  • If, after performing a smoke test, the vacuum system is found to have leaks, the mechanic should repair any leaks they find.

Additional comments for consideration regarding the P1100 code

Mechanics should keep in mind when removing the MAF sensor to take care not to touch the wires connected to the MAF sensor. While the wires cannot electrocute the mechanic, these wires are delicate and easily broken.

Need help with a P1100 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.

P1100
trouble codes
OBD-II

Fast and easy Check Engine Light is on Inspection service at your home or office.

SCHEDULE P1100 DIAGNOSTIC
Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.5/5

Number of Reviews

3,936

Rating Summary
3,597
169
44
25
101
3,597
169
44
25
101

David

23 years of experience
50 reviews
David
23 years of experience
David was very patient while doing his job never complaining and working to get the job done I was very impressed with his professionalism
2004 DODGE RAM 1500 - CHECK ENGINE LIGHT IS ON - KYLE, TEXAS

Keith

8 years of experience
16 reviews
Keith
8 years of experience
Keith- professional, courteous, competent and really did a great job he's welcome back anytime
2004 CHEVROLET IMPALA - CHECK ENGINE LIGHT IS ON - CONROE, TEXAS

Joseph

17 years of experience
285 reviews
Joseph
17 years of experience
Seemed competant
1999 CHEVROLET TAHOE - CHECK ENGINE LIGHT IS ON - LAYTON, UTAH

Stefan

14 years of experience
366 reviews
Stefan
14 years of experience
Stefan explained the findings well and I was very happy overall with his visit. But I'm disappointed that I haven't received any follow up from the company in the 6 hours since the visit. They charged my card for the diagnostic shortly after the visit but they haven't followed up, letting me know the estimate to fix the car, or at least that an estimate is being created, and a time frame for getting the estimate. So I have a diagnostic but also a car in my driveway that I can't drive, and no communication about the next step.
1994 BMW 530I - CHECK ENGINE LIGHT IS ON - PLEASANTON, CALIFORNIA

More related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0121 OBD-II Trouble Code: TPS "A" Circuit Range Performance Problem
P0121 code definition Throttle Pedal Position Sensor/Switch (TPS) A Circuit Range Performance Problem...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...

Related questions

Q: The engine light is blinking, the car jolts when it car accelerates. And the engine songs like it wants to shut off sometimes

The flashing Check Engine Light tells me that the engine is having a misfire condition occurring. This could be due to bad spark plugs or ignition coils as well as other sensor on the engine reading incorrectly. There will be...

Q: What Is the OBD II System on My Car?

OBD II is an abbreviation of on board diagnostic system generation two. The system was brought into service in the vehicles of model year 1996. The system was put into all vehicles to monitor the operation and control the engine...

Q: Check Engine Light code P2544

The short answer is yes, the tire size can cause the P2544 code. This code sets when the computer sees that the vehicle speed and the requested torque tables in the transmission control module don't coincide. So, a different tire...

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.

1-800-701-6230 · hi@yourmechanic.com