P0107: MAP / Barometric Pressure Circuit Low Input
TL;DR
P0107 = MAP/BARO circuit low input. Severity: medium. Top causes: faulty MAP sensor (35%), wiring short to ground (25%), disconnected/leaking vacuum hose (25%), connector fault (15%).
Can I keep driving with P0107?
IF it runs acceptably → drive briefly to diagnose; check the vacuum hose first. IF it hesitates badly, stalls or is hard to start → drive minimally, since fueling is based on a bad load signal.
Symptoms
- Check engine light on
- Hard starting
- Hesitation or stumbling
- Reduced power
- Worse fuel economy
Top causes (ranked by probability)
| Likely cause | Probability | Notes |
|---|---|---|
| Faulty MAP sensor | 35% | |
| Signal wire short to ground | 25% | |
| Disconnected or leaking vacuum hose | 25% | Check this first — quick and common |
| Connector fault | 15% |
What does P0107 mean?
Technical explanation
P0107 sets when the MAP sensor signal voltage stays below the expected range. Causes include a failed sensor, a signal-wire short to ground, an open 5 V reference, or a disconnected/leaking vacuum supply that makes the sensor read implausibly low pressure. Because the ECM uses MAP to estimate load, a low signal causes incorrect fueling — typically lean, with hesitation and hard starting.
In simple terms
The MAP sensor measures intake pressure so the computer can fuel the engine correctly. P0107 means it’s reading too low — often a wiring short, a disconnected vacuum hose, or a bad sensor. The car may run poorly, be hard to start and use more fuel.
How to diagnose P0107 (step by step)
- Read MAP live data. A reading stuck low (with low voltage) confirms it.
- Check the MAP vacuum hose. A disconnected or leaking hose makes the sensor read low.
- Check wiring for a short to ground. A grounded signal wire pulls the reading low.
- Verify the 5 V reference and ground. Confirm power and ground to the sensor.
- Replace the MAP sensor if faulty. If wiring and vacuum are good, replace the sensor.
Repair options & cost
- Replace the MAP sensor
- Repair the wiring short
- Reconnect/replace the vacuum hose
- Repair the connector
🔧 Doing it yourself? Buy the part: MAP (manifold pressure) sensor
| DIY cost | $15–$120 |
|---|---|
| Workshop cost | $90–$350 |
| Repair time | 20–60 minutes |
Costs are local ballpark ranges and vary by region and vehicle.
Tools you’ll need
Scan your car: recommended OBD-II scanners →Vehicle-specific notes
- Check the MAP vacuum hose first — a disconnected or cracked hose is a quick, common cause.
- P0107 (low) is the opposite of P0108 (high).
- Confirm the 5 V reference; an open reference can drive the signal low.
Common mistakes to avoid
- Replacing the sensor while the vacuum hose is off/cracked
- Missing a signal-wire short to ground
- Overlooking an open reference voltage
- Ignoring a corroded connector
Frequently asked questions
What causes a P0107 code?
A faulty MAP sensor, a signal-wire short to ground, a disconnected/leaking vacuum hose, or a bad connector. Check the vacuum hose first — it’s a quick, common cause.
Is P0107 the same as P0108?
They’re opposites: P0107 is a low MAP signal, P0108 is a high one. Both point to the MAP sensor, its wiring, or the vacuum supply.
Can I drive with P0107?
Short-term if it runs acceptably, but expect poor performance and hard starting. If it stalls, drive minimally and fix it.
P0107 summary
| Meaning | MAP/BARO circuit low input |
|---|---|
| Severity | Medium |
| Safe to drive? | Caution |
| Top cause | Faulty MAP / vacuum hose (60%) |
| DIY cost | $15–$120 |
| Shop cost | $90–$350 |