2020-2025 Audi Fuel System DTC P014800 P008700 TSB

Owners of certain 2020-2025 Audi vehicles may encounter issues with their fuel system, leading to warning lights and reduced engine performance. This Technical Service Bulletin (TSB) 2079461/1 outlines the diagnostic and repair steps for conditions where Diagnostic Trouble Codes (DTCs) P014800 or P008700 are stored in the Engine Control Unit (ECM).

This bulletin specifically addresses concerns related to the high-pressure fuel pump, which can manifest as unusual noises or vibrations from the engine's fuel supply system. Understanding the symptoms and recommended repair procedures is crucial for addressing this Audi fuel system DTC P014800 issue effectively.

Symptoms

Owners may notice one or more of the following symptoms if their vehicle is affected by this fuel system concern:

• The Malfunction Indicator Lamp (MIL) illuminates, commonly known as the "Check Engine" light. The verbatim message displayed is often "MIL light is on".
• The vehicle's performance is restricted, and it enters a reduced power or "limp-home function activates" mode. This safety feature limits engine output to prevent further damage.
• Audible noises or vibrations originating from the high-pressure fuel pump area, described as "high-pressure fuel pump noises, vibrations -> too loud" in the complaint type.

Fault Codes / DTCs

When diagnosing the issue, technicians will typically find one or both of the following Diagnostic Trouble Codes (DTCs) stored in the Engine Control Unit (ECM) -J623- (address word 0001):

Code	Description
P014800	Fuel Delivery Error
P008700	Fuel Rail/System Pressure - Too Low

These codes specifically point to problems with the fuel delivery system, particularly concerning the pressure within the fuel rail. The TSB notes that P008700 can be active/static with symptom 15059 and status 11101101.

Diagnosis and Trigger Conditions

The diagnostic process for an Audi fuel system DTC P014800 or P008700 begins by clearing the stored DTCs from the Engine Control Unit. If these DTCs reappear after clearing, further investigation is required. Technicians should then perform tests related to the low-pressure fuel pump, as detailed in the ELSA repair manual. These initial tests include "Checking fuel delivery rate" and "Pressure test in the fuel supply line."

If the concern is reproducible or static, a more in-depth procedure is followed. This involves installing a specialized tool, the VAS 6550 pressure gauge, on the low-pressure side of the fuel system, specifically just before the high-pressure fuel pump. This setup allows for continuous monitoring of the in-line fuel pressure on the low-pressure side while the engine is running.

Concurrently, the ODIS-S diagnostic software is used. Technicians must select the self-diagnosis function within ODIS-S and set up a graph of "measured high-pressure measured values (Actual VS. Specified)". This graphical display allows for real-time monitoring of the in-line fuel pressure on the high-pressure side while the engine is in operation.

During engine operation, the in-line fuel pressures on both the high and low sides are closely monitored. The key diagnostic thresholds for determining if the high-pressure fuel pump needs replacement are:

• If the pressure on the low side does not drop below 3 bar.
• If the pressure on the high side does not exceed 20 bar.

If both of these conditions are met, the high-pressure fuel pump should be replaced. This indicates that the pump is not maintaining adequate pressure within the specified ranges.

For repeat repairs where the concern is not consistently reproducible, technicians will examine the expanded ambient conditions associated with the DTCs P014800 and P008700. If the fuel rail pressure on the high-pressure side is approximately 10 bar, the high-pressure fuel pump is the primary suspect and should be replaced before considering any other parts connected to the fuel system. An example provided in the TSB illustrates a scenario where the actual fuel pressure at the rail is 880 kPa (8.8 bar) compared to a specified value of 243.5 bar, indicating the high-pressure fuel pump would need replacement.

Repair Procedure Summary

The primary repair for this Audi fuel system DTC P014800 issue, as outlined in TSB 2079461/1, focuses on the diagnosis and potential replacement of the high-pressure fuel pump. After confirming the presence and recurrence of DTCs P014800 or P008700, and performing the detailed pressure tests using the VAS 6550 gauge and ODIS-S software, the decision to replace the high-pressure fuel pump is made based on the observed pressure readings and specific thresholds.

The repair process typically involves accessing and removing the faulty high-pressure fuel pump and installing a new one. Depending on the vehicle configuration, this may also include removing and installing the air filter housing, especially in gasoline engines. The TSB provides specific labor operations and associated times for these tasks to ensure efficient and accurate repair by qualified technicians.

Required Tools or Parts

Accurate diagnosis and repair of this fuel system issue require specialized equipment:

• VAS 6550 pressure gauge: Used for precise measurement of fuel pressure on the low-pressure side of the system, installed just before the high-pressure fuel pump.
• ODIS-S diagnostic software: Essential for monitoring in-line fuel pressures, comparing actual versus specified values, setting up graphical displays, and clearing DTCs.
• ELSA repair manual: Referenced for detailed procedures on testing the low-pressure pump, including "Checking fuel delivery rate" and "Pressure test in the fuel supply line."

Specific part numbers for the high-pressure fuel pump are not listed in the TSB but would be determined by the technician based on the vehicle's VIN and model.

Warranty Information

This Technical Service Bulletin provides detailed information for warranty claims related to the fuel system issue. The Claim Type specifies that "If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only." This means that repairs performed under the guidance of this TSB may not be covered by Audi and could incur costs for the owner. All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual.

• Service Number: 2374
• Damage Code: 0010
• Claim Comment: As per TSB 2079461/1

Labor Operations

The following labor operations are specified for addressing this issue:

Labor Operation	Code	Time Units (TU)	Notes
Remove and install high-pressure pump	2463 19XX	See SRT	With associated operations
Remove and install 2 high-pressure pumps	2463 20XX	See SRT	With associated operations
Check fuel pump	2066 0199	50 TU
Remove and install cover	1083 1900	See SRT	With associated operations
Remove and install air filter housing (gasoline engines)	2425 19XX	See SRT	With associated operations
GFF/ Guided Functions	0150 0060	Time stated	On the diagnostic protocol

Owner Action

If your 2020-2025 Audi is displaying a "MIL light is on" or entering a "limp-home function activates" state, especially if accompanied by unusual engine noises, it is crucial to have your vehicle inspected by an authorized Audi service center. Inform the technician about the symptoms you are experiencing and mention the possibility of an Audi fuel system DTC P014800 or P008700.

Since this is a Technical Service Bulletin and not a recall, Audi may not directly notify owners. It is the owner's responsibility to seek diagnosis and repair. Ensure that any repairs are performed according to the procedures outlined in TSB 2079461/1 to correctly address the fuel system issue.

NHTSA ID: 11025286