Audi 80 Quiz
Engines

Troubleshooting

In this manual: Engines
Technical Description — 39Engines — 41Exhaust System — 13Cooling System — 28Fuel tank and fuel pump — 12Air Filter and Intake Ducts — 13Mono-Motronic Injection System — 18Digifant Injection System — 19KE-III-Jetronic Injection System — 35MPI and MPFI Injection Systems — 32Clutch — 11Transmission and Driveline — 21Suspension and Steering — 33Brake System — 41Anti-lock brake system — 8Wheels and Tires — 13Body Electrical System — 35Ignition System — 24Lighting — 14Signaling Devices — 7Instruments and Auxiliary Equipment — 54Heating and Ventilation — 7Body Components — 18Troubleshooting — 6Specifications — 13
~1min read

To more precisely determine the cause of low compression pressure, use the following method: add a small amount of oil from the oil can through the spark plug hole and measure the pressure again.


If the readings are still low, the cause is the valves.

If you obtain higher readings, the cause is the piston rings or possibly the cylinders. The added oil temporarily improved the seal between the pistons and cylinder walls, so the compressed gas could barely escape.

Test yourself

A quick Audi 80 quiz: every answer comes with an explanation and a link to the manual page.