Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSAUDI199590 BASE, 2.8 K, AUTOMATICREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISENGINE CONTROLS - SYSTEM/COMPONENT TESTSFUEL SYSTEMFUEL PRESSURESYSTEM PRESSURE
1995 Audi 90 Base, 2.8 K, Automatic
System Pressure
1995 Audi 90 Base, 2.8 K, AutomaticSECTION System Pressure
- Ensure fuse No. 13 (fuse No. 17 on A6 model) is okay, fuel filter is in good condition and battery voltage is 12 volts minimum. See ELECTRICAL COMPONENT LOCATIONS . Connect Pressure Gauge (VAG 1318) between fuel supply line and fuel rail. Open pressure gauge lever. Disconnect vacuum hose from fuel pressure regulator. Plug open end of vacuum hose.
- Initiate OUTPUT DTM. See TESTS W/CODES article. Activate fuel pump relay. If fuel pump does not operate, check fuel pump. See FUEL DELIVERY . If fuel pump operates, check fuel pressure. If fuel pressure is 55-61 psi (3.8-4.2 kg/cm2 ), go to step 4).
- If fuel pressure is not as specified, replace fuel pressure regulator and recheck pressure. If fuel pressure is less than specified, check for damaged fuel pump or restricted fuel supply line. If fuel pressure exceeds specification, check for restricted fuel return line.WARNING: Excessive fuel pressure may rupture fuel pressure regulator diaphragm, causing fuel to enter engine through vacuum hose. This could result in an explosion.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.