Fuel and exhaust system specifications (Audi 80 B3)

Air filter

Type - Replaceable paper element, with automatic air temperature control on most models

Filter element:

• Carburetor engines - Champion W102
• 1.6 liter fuel injection engine - Champion U506
• All other fuel injection engines - Champion U501

Fuel system

Fuel pump:

• Carburetor engines - Mechanical, diaphragm, driven by an eccentric from an intermediate shaft
• Fuel injection engine - Electric fuel pump with circulation chamber

Working pressure on a carburetor engine is 0.35 - 0.40 bar

Fuel tank capacity

• All models except Coupe - 68 hp.
• Coupe — 70 l.

Carburetor system

Engine:

• RN and NE — Keihin I
• RU — Keihin II

Carburetor (Keihin I)

Type - Two-chamber with falling flow and mechanical damper

Jets and purposes:	RN Engine	NE Engine
Increased idle speed	3200±200 rpm	3200±200 rpm
Accelerator pump injection	0.78±0.12 cm³/stroke	0.78±0.12 cm³/stroke
Air damper clearance	4.6±0.15 mm	4.6±0.15 mm
Idle speed	900±50 rpm	900±50 rpm
CO content	1.0-0.5%	1.0-0.5%
Diffuser - Chamber 1/2	20/26	20/26
Main Jet - Chamber 1/2	108/150	110/150
Correction Air Jet - Chamber 1/2	90/120	90/120
Idle fuel jet	52	52
Idle air jet	115	115
Float regulator shut-off needle valve	2.5	2.5

Carburetor (Keihin II)

Type - Double chamber with falling flow and mechanical damper

Jets and Purposes - Engine RU:

• Increased idle speed - 3500±200 rpm
• Accelerator pump injection - 0.85±0.15 cm³/stroke
• Air damper clearance - 2.2±0.15 mm
• Idle speed - 900±50 rpm
• CO content - 1.0-0.5%
• Diffuser - Chamber 1/2 - 22/26
• Main Jet - Chamber 1/2 - 100/140
• Correction Air Jet - Chamber 1/2 - 90/100
• Idle Fuel Jet - Chamber 1 - 50
• Idle Air Flow - Chamber 1 - 100
• Float regulator shut-off needle valve - 2.5
• Exhaust Pipe - Chamber 1 - 40
• Enrichment - Chamber 1 - 35

Fuel injection system

Engine:

• PS (before 1989), DZ and KV — K-Jetronic
• PS (since 1989) and JN - KE-Jetronic
• PM — Mono-Jetronic
• NG — KE III-Jetronic
• PROS — KE-Motronic
• 7A - Multi-Point Injection (MPI)

Engine DZ - K-Jetronic

Idle speed - 950±30 rpm

CO content - 1.3±0.2%

Increased idle speed:

• Switching frequency - 700 rpm
• Switch-off frequency - 1050 rpm

Maximum fuel pump speed - 6500 - 6700 rpm

System pressure - 5.2 - 5.9 bar

Residual pressure (in 10 minutes) — 3.3 bar

PS (up to 1989) and KV engines - K-Jetronic

Idle speed - 750-850 rpm

Current in the idle control circuit - 430-440 mA

CO content - 1.0-1.2%

System pressure - 5.4-6.2 bar

Residual pressure (in 10 minutes) — 3.4 bar

PM Engine - Mono-Jetronlc

Maximum rotation speed - 6300 rpm

Idle speed - 750-950 rpm

CO content - 0.2-1.2%

System pressure - 0.8-1.2 bar

Residual pressure (in 5 minutes) minimum - 0.5 bar

Injector resistance - 1.2-1.6 Ohm

JN Engine - KE-Jetronic

Idle speed - 900±30 rpm

CO content - 0.3-1.2%

Increasing idle speed:

• Switching frequency - 700 rpm
• Switch-off frequency - 1050 rpm

Maximum frequency (fuel pump relay) — 6270-6330 rpm

System pressure - 5.2-5.6 bar


Residual pressure - 2.6 bar

Injector injection pressure - 3.5-4.1 bar

PS Engine (since 1989) - KE-Jetronic

Idle speed - 750-850 rpm

CO content - 0.3-1.2%

System pressure - 6.1-6.5bar

Residual pressure (in 10 minutes) — 3.4 bar

Injector injection pressure - 4.3-4.6 bar

Engine NG - KE III-Jetronic

Idle speed - 720-860 rpm

CO content:

• Lambda sensor disabled - 0.8±0.3%
• Lambda sensor on - 0.3-1.2%

Frequency limitation (control unit) — 6500-6700 rpm

System pressure - 6.1-6.5 bar

Residual pressure:

• After ten minutes - 3.5 bar
• After twenty minutes - 3.4 bar

Injector injection pressure - 4.3-4.6 bar

Engine ZA - KE-Motronic

Idle speed - 780-900 rpm

CO content - 0.2-1.2%

Control current of CO content - 0-5 mA

Frequency limit - 6300-6500 rpm

System pressure - 6.1-6.5 bar

Residual pressure:

• After ten minutes - 3.3 bar
• After twenty minutes - 3.2 bar

Injector injection pressure - 3.7-4.8 bar

Engine 7A - Multi-point injection (MPi)

Idle speed - 800±50 rpm

CO content - 0.75-0.25%

System pressure - 3.8-4.2 bar

Residual pressure:

• After ten minutes - 3.2 bar
• After twenty minutes - 3.0 bar

Tightening torques, Nm

• Front Exhaust Pipe Installation - 30
• Fuel pump bolts - 20
• Fuel tank - 25
• Exhaust manifold - 25
• Exhaust pipe - 40
• Heating valve - 10
• Cold start valve - 10
• Fuel filter connection - 20
• CO measuring pipe - 30
• Exhaust outlet pipe to manifold - 35
• Lambda sensor to catalytic converter - 50
• Carburetor flange - 13
• Intake manifold - 25
• Intake to exhaust manifold hanger - 20
• Inlet air heater - 10
• Carburetor cover - 5
• Measurement pipe - 20
• Fuel start switch - 30
• Throttle body - 20
• Diaphragm pressure regulator connection - 20

[The original article is available on the website audimanual.ru]