P2199

Intake Air Temperature Sensor 1/2 Correlation

Q: Is it safe to drive with P2199?

Yes. Intake-air temperature is a minor fueling input, so the effect is small — mainly slightly off cold-start fueling and economy. Still, repair it to keep the mixture accurate.

Q: Can I just clear P2199?

It clears, but if one sensor is drifting or a connection is poor the mismatch returns. Identify and replace the out-of-range sensor first.

Fuel & air metering Generic OBD-II Low

What it means

P2199 means the two intake-air temperature (IAT) sensors are reporting temperatures that disagree by more than the ECM allows. After the engine has sat and cooled, both should read close to the same value, so a mismatch points to one sensor drifting or a wiring problem. IAT is only a minor fueling input, so the car drives normally — the main effect is slightly less accurate cold-start fueling.

Low

Can I keep driving? Safe to drive — a mismatch between the two intake-air temperature sensors has only a minor effect on cold-start fueling and economy; there is no immediate risk.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Often no noticeable driving symptom
Slightly rough or richer cold start
Minor drop in fuel economy or throttle response

Common causes

Most likely first

One intake-air temperature sensor drifting out of calibration (IAT 1 or IAT 2, the latter often built into the MAF)Likely
Open, shorted, or high-resistance wiring at one IAT sensorCommon
Poor electrical connection or corrosion at a sensor connectorCommon
A genuine temperature difference between sensor locations after a repair or relocationLess often
Faulty ECM (least likely)Less often

How to diagnose & fix

Work through it in order

With the engine cold and off overnight, compare both IAT readings on a scan tool — after a cold soak they should read within a few degrees of each other.
Inspect the wiring and connectors at both sensors for corrosion, damage, or loose pins.
Measure each sensor's resistance and compare it to the temperature-vs-resistance spec.
Replace whichever sensor reads out of range (IAT 2 may mean replacing the MAF if it is integrated), then clear and re-test.

FAQ

Quick answers

Is it safe to drive with P2199?+

Yes. Intake-air temperature is a minor fueling input, so the effect is small — mainly slightly off cold-start fueling and economy. Still, repair it to keep the mixture accurate.

Can I just clear P2199?+

It clears, but if one sensor is drifting or a connection is poor the mismatch returns. Identify and replace the out-of-range sensor first.

Read & clear P2199 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX