Peugeot 907 P1799 Engine Trouble Code
What is Peugeot 907 P1799?
With Peugeot 907 P1799, you may drive for several weeks with a malfunctioning MAF sensor, but expect decreased fuel economy and eventual stalling. Shop replacement costs $240–$400 depending on vehicle. The labour is straightforward, with most cost from the part itself.
P1799 on the Peugeot 907
In cold climates, Peugeot 907 vehicles frequently log P1799 during the first winter of ownership. Condensation inside the throttle body creates a temporary short circuit in the position sensor wiring, which clears once the engine warms up — but the fault code remains stored.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Vehicle: | Peugeot 907 |
| Brand: | Peugeot |
| Model: | 907 |
| Code: | P1799 |
P1799 Peugeot 907 Symptoms
Check Engine Light
Illuminated Peugeot 907 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Peugeot 907
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Peugeot 907
Increased Emissions
Failed emissions test due to P1799
P1799 Code Structure
Understanding what each digit means in the P1799 powertrain trouble code:
| P | 1 | 7 | 9 | 9 |
|---|---|---|---|---|
| Powertrain Code | Fuel And Air Metering | Fuel Rail Pressure Sensor Circuit Malfunction | Crankshaft Position Sensor A Circuit Malfunction | Reverse Input Circuit |
How to Fix Peugeot 907 P1799
Diagnostic Steps:
Poor running symptoms align with MAP sensor malfunction. In some cases, a faulty MAP sensor will not trigger a code. The issue may represent separate wiring concerns requiring individual diagnosis.
Repair Solution:
Crankshaft position sensor signals the computer for precise ignition and fuel injection timing. Faulty sensors cause rough running and reduced efficiency. Modern vehicles enter limp mode and illuminate the check-engine light.
Technical Notes:
Parts or components should not be replaced based solely on P1799 DTC. Consult your vehicle service manual for proper diagnostic procedures, possible causes, and required testing before replacement.
Peugeot 907 P1799 Repair Cost
PCV system overhaul on the Peugeot 907 — which resolves oil-mist contamination of the MAF sensor — costs $100–$200. The MAF sensor should be cleaned ($15–$25 DIY) or replaced ($80–$150) at the same time to ensure accurate fuelling after the fix.
P1799 Description
P1799 engine trouble code is related to Reverse Input Circuit.
Main Cause
The primary reason for P1799 OBD-II Engine Trouble Code is: Fuel Rail Pressure Sensor Circuit Malfunction.
Common P1799 Misdiagnosis on the Peugeot 907
When Peugeot 907 presents P1799 with a concurrent coolant temperature DTC, technicians sometimes replace the thermostat rather than the coolant temperature sensor (CTS). The CTS is a $15–$25 component; the thermostat job carries 1–2 hours of additional labour.
DIY Repair Guide: P1799 on Peugeot 907
The coolant temperature sensor on the Peugeot 907 is a straightforward DIY item (difficulty 2/5). Have a drain tray ready for the small amount of coolant that spills when the sensor is removed. Top up the cooling system afterwards and check for air pockets.
Preventing P1799 on the Peugeot 907
Inspecting the Peugeot 907 wiring harness conduit grommets annually — especially the floor pan grommet — costs nothing and takes 10 minutes. Catching moisture ingress early eliminates the most common electrical trigger for P1799 on this model.
Frequently Asked Questions — Peugeot 907 P1799
A: It depends on the severity. If the check-engine light is steady, it is generally safe to drive to a workshop within the next few days. If the light is flashing, pull over safely as soon as possible — a flashing light indicates an active misfire that can cause expensive catalytic converter damage within minutes.