Table of contents: Engine crankshaft speed control at… ↓ Adjustment of carbon monoxide (CO)… ↓
Engine crankshaft speed control at idle
Connect the tachometer according to the operating instructions.
Turn on the high beam headlights.
Start the engine and increase the crankshaft speed to 3000 rpm, after 30 seconds reduce the engine speed to idle, i.e. to 900-1000 rpm.
Note: If the injector fuel lines have been disconnected or replaced before adjusting the engine idle speed, run the engine several times at 3000 rpm and idle.
Set the idle speed of the crankshaft within 900-1000 rpm using the adjusting screw 1 (see photo), located on the throttle body.
Section of the mixture regulator: 1 - air flow meter diffuser; 2 - pressure disk; 3 - lever system; 4 - counterweight; 5 - distribution plunger; in - fuel dispenser-distributor.
Adjustment of carbon monoxide (CO) content in exhaust gases
Note: When adjusting the CO content, do not push or pull the adjusting screw. After inserting the socket wrench into the screw head, do not press the accelerator pedal to avoid damaging the adjusting screw.
Connect the gas analyzer according to the operating instructions.
Remove the plug of the mixture quality adjustment screw located on the fuel dispenser-distributor (see photo).
The operating principle of the fuel dispenser: 1 - valve spring; 2 - diaphragm; 3 - distribution plunger; 4 - slotted sleeve of the distribution plunger; 5 - lower chamber; 6 - upper chamber; 7 - fuel supply to the injectors; 8 - control edge of the distribution plunger.
Using a socket wrench, turn the mixture quality adjustment screw until the CO content is within 1.0-2.0%.
When the screw is turned clockwise, the CO content in the exhaust gases increases, and vice versa.
If it is necessary to turn the adjusting screw several times in one direction or another to achieve the desired CO content, then after each adjustment it is necessary to remove the key and lightly press the accelerator pedal.
After adjustment, install a new plug on the mixture quality adjustment screw.
After adjusting the engine idle speed, connect the engine crankcase ventilation hose.
The text is based on materials from the website AudiManual