B5 S4 2.7T Biturbo · Owner's Reference
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Audi S4 2.7 V6 Biturbo

Everything for your 2001 S4 on one page: specs, diagrams, the 6-speed 01E gearbox, calculators, a service tracker, symptom finder, known weak points and one-click access to your whole factory manual library.

Output
250 hp @ 5,800
Torque
258 lb-ft @ 1,800
Displacement
2,671 cc
Gearbox
6 -speed 01E
Final drive
4.11 : 1 ≈
Firing order
1-4-3-6-2-5

My car — enter your VIN and the whole guide adapts (saved in this browser only)

Decode checks the VIN offline (year, plant, check digit) and, only if you agree, also asks the free NHTSA vPIC database for model/engine details. Engine and transmission can always be set by hand; the guide, specs and manual library filter to your selection.

How to use this page: press / to search everything (specs, problems, and the PDF manual library). Figures marked ≈ are typical values from experience/industry sources — always confirm torque specs and critical clearances in the factory PDFs linked in each section.

1 Quick specs

Your factory manual (APB, 09.1999→) and the common European variants side by side.

Engine · US-spec APB (from factory manual 00-1)
Engine codeAPB (build from 09.1999)
Capacity2,671 cc (2.7 L)
Power250 hp @ 5,800 rpm
Torque258 lb-ft @ 1,800–4,500 rpm
Bore × stroke81.0 × 86.4 mm
Compression9.3 : 1
Fuel98 RON min. (95 RON usable, power loss) · US: premium 91+ AKI
Firing order1-4-3-6-2-5
Engine managementMotronic, closed-loop lambda, on-board diagnostic
Cam timing controlYes (intake variable) · Secondary air: no · EGR: no
TurbochargingYes – twin turbo · catalytic converters: yes
Valve timing (1 mm lift, 0 mm clearance, VVT inactive)
Inlet opens10° after TDC
Inlet closes20° after BDC
Exhaust opens38° before BDC
Exhaust closes8° before TDC
European variants ≈
AGB (1997–2000)265 PS / 195 kW @ 5,800 · 400 Nm @ 1,850–3,600
ARY (2000–2002)265 PS · same output, updated ECU/emissions
Block / headsCast-iron block · aluminium 5-valve DOHC heads
Car ≈
ChassisAudi A4 / S4 Typ 8D (B5), sedan & Avant
DrivetrainLongitudinal V6, quattro (Torsen centre diff)
Gearbox6-speed manual 01E (see gearbox section) · Tiptronic 01V was the auto option
Kerb weight≈ 1,550–1,650 kg (sedan / Avant)
0–60 mph≈ 5.4–5.8 s
Wheels5 × 112 · centre bore 57.1 mm · bolts M14 × 1.5 (≈120 Nm / 89 lb-ft)
Front brakes≈ 312 mm vented discs (S4)

Jump to the source documents

Technical data pages, straight from your library:

2 Engine layout & firing order

90° V6 viewed from above. Cylinders 1-2-3 sit on the right bank, 4-5-6 on the left bank (numbering from the front/belt end). The engine number is stamped on the block at the front of the right bank.

REAR · bell-housing / gearbox LEFT BANK RIGHT BANK Cyl 6fires 4th Cyl 5fires 6th Cyl 4fires 2nd Cyl 3fires 3rd Cyl 2fires 5th Cyl 1fires 1st 90° V · intake manifold in the valley FRONT · belt end Firing order 1 → 4 → 3 → 6 → 2 → 5
Schematic cylinder layout (top view). Firing order from factory data 00-2.

Firing sequence

143625

Coil-on-plug: 6 individual coils with integrated output stages. Misfire on one cylinder = check that coil + plug first (swap coils between cylinders to confirm).

Where's the engine code?

Machined surface on the block, front of the right cylinder bank (code + serial, e.g. APB 000 405). Also on the vehicle data sticker (spare-wheel well / service book).

3 Timing drive

A toothed belt drives the exhaust camshafts (and water pump); short chains link each exhaust cam to its intake cam, which carries the variable-timing adjuster.

LEFT BANK RIGHT BANK INT L INT R EXH L EXH R Water pump Crank tensioner idler toothed belt cam chain (per bank) exhaust cam
Simplified schematic — not to scale and not a timing-marks reference. Use manual 15-1 / 13-1 before touching timing.

Timing belt service ≈

  • Change belt every ~60–75k miles or 6 yrs (earlier is cheaper than an engine).
  • Always replace tensioner, idler(s), water pump and thermostat at the same time.
  • Inspect cam chains/guides while the covers are off; rattle on cold start = look at chain tensioners.
  • Interference engine — a snapped belt usually bends valves.

Variable cam timing

Hydraulic adjusters on the intake cams, controlled by solenoids (N205/N208). Clean oil matters: dirty oil = sticky solenoids and rough idle or cam-timing DTCs.

4 Air & boost path

Twin parallel turbochargers (one per bank), two side-mounted intercoolers in the front bumper corners, a single drive-by-wire throttle body, and recirculation (diverter) valves to protect the compressors when you lift.

▶ INTAKE (cold side) ◀ EXHAUST (hot side) Air boxfilter MAF ×2G70 / G246 CompressorsK03 ×2 (turbo) Intercoolersside-mount ×2 Throttledrive-by-wire Intakemanifold V6engine shared shaft (turbo) Cats+ muffler Downpipes×2 Turbines+ wastegates Exh. manifoldscast, per bank Diverter / N249recirculation valves N75 boost solenoidsets wastegate pressure
Flow overview. Each bank has its own turbo, intercooler and (typically) its own recirculation valve; the paths merge at the throttle body. A boost leak anywhere on the blue side = low boost, lean codes or limp mode.

Stock boost ≈

Peak ≈ 0.8–1.0 bar (12–15 psi) absolute-gauge, tapering at high rpm. Anything far below usually = leak, sticky diverter or N75/wastegate issue.

Fast leak hunt

  • Smoke-test the charge system (best).
  • Check intercooler end-tanks & hose clamps.
  • Inspect all vacuum lines at the manifold & diverters.

5 Power & torque

A wide, flat torque plateau (1,800–4,500 rpm) is the characteristic of the twin-small-turbo setup — light spool, plenty of midrange.

1000200030004000500060007000 engine speed (rpm) torque plateau 1,800–4,500 250 hp @ 5,800 258 lb-ft torque power
Illustrative shape built from the published peak figures (not a measured dyno run).

6 Quattro drivetrain

Longitudinal engine → 6-speed manual (01E) or 5-speed Tiptronic (01V) → Torsen centre differential → front and rear final drives.

FRONTREAR 2.7T V6longitudinal Gearbox01E / 01V Torsencentre diff rear diff front diff / drive Simplified power flow — not exact component packaging
Torsen centre diff splits torque ≈ 50/50 by default and shifts it automatically to the axle with grip.

Transmission manuals in your library

Your folder covers the 5-speed 01A/01V family (related quattro final-drive and Torsen procedures). For your 6-speed 01E, start with the 01E section below.

Clutch & flywheel notes ≈

  • Dual-mass flywheel: rattle at idle/shutdown = wear.
  • Hydraulic clutch: bleed with DOT 4 (shares brake fluid).
  • Stock clutch is the first thing to slip on a tuned car.

7 Gearbox — 01E 6-speed manual

The S4's 6-speed (VW/Audi code family 01E, the same unit family as the RS4 but with different 3rd/4th ratios) bolts straight to the engine and feeds the Torsen centre diff. Ratios below are community-sourced ≈ — confirm with the code stamped on your own gearbox.

GearRatio ≈Overall (× 4.11)
Top speed available in each gear at the rpm you choose in the calculator below (updates live).

Identification

  • Family: 01E (6-speed, longitudinal, quattro).
  • Community lists the S4 box as ID DSY (RS4 = FDP) ≈ — your 2001 US-spec code may differ.
  • Final drive: 4.111 (37:9) ≈.
  • Code is stamped on the case near the bell-housing; also on the build sticker.

Gear oil

  • Synthetic 75W-90 to VW spec G 052 911 A2 (or equivalent, e.g. Castrol Syntrans/ Pentosin).
  • Fill ≈ 3.4–3.5 L (includes ~0.3 L for oil cooler & lines) — fill to the filler hole.
  • Front diff and rear diff have their own oil — change all three.

01E documents

External link — it isn't in your local folder. Save it into Transmission and I can add it to the library.

8 Gear & speed calculator

Pick tyre size, final drive and rpm to see road speed in every gear. Great for gearing up/down, tyre swaps and checking speedometer error.

Ignores clutch slip, tyre growth and speedometer error. Default tyre ≈ 235/40R17 (common S4 size).

9 01E care & weak points

What owners and rebuilders report on the 6-speed. Forum-sourced — treat as guidance, not factory data.

fix soon 1st/2nd gear synchros
Symptoms: crunch or resistance going into 1st/2nd, popping out of gear. Notes: the most-reported 01E fault; Audi later revised the synchro parts (coated/updated). Fix: rebuild with updated synchros — needs the box out. Rule out clutch drag and old gear oil first.
watch Clutch, flywheel & hydraulics
Slip under boost = tired clutch (common on tuned cars). Chatter/clunk at idle or shut-down = dual-mass flywheel wear. Soft pedal or hard-to-select gears can be the hydraulic system — bleed with DOT 4, replace slave/master if leaking. Replace clutch, flywheel and release bearing together.
watch Sloppy shifter / linkage bushings
Vague or notchy shifts are usually worn shifter and linkage bushings, not the box. A bushing refresh plus fresh gear oil often transforms the feel. Inspect before assuming internals are bad.
watch Whine, bearings & leaks
Whine in a gear or on overrun can be input/pinion bearings; oil seeping from flange seals or the oil cooler lines is common with age. Check oil level and condition (metal glitter = wear). Cooler lines (≈0.3 L circuit) can leak — inspect hoses/clips.
info Torque tolerance
Stock-to-moderate tunes are fine on a healthy box; the clutch gives up long before the gearbox. Rebuilders describe the 01E as strong but its syncros are marginal when abused and the pinion bearings are often worn — refresh both before big power. Far higher torque (≈650 lb-ft) is called "edge of safe" by builders of diesel swaps.
Fluid change recipe: warm car → level car on ramps → remove filler plug first (so you can refill) → drain → refit drain with new seal → pump in oil until it weeps from the filler hole → repeat on front and rear diffs. Use fresh sealing washers.

10 Maintenance schedule

Practical intervals for a ~25-year-old turbo V6 (≈ conservative, specialist-style). Check "Maintenance" PDFs in your library for the factory schedule.

ItemInterval ≈
Engine oil + filter5,000 mi / 6 mo (turbos like fresh oil)
Spark plugsevery 30k mi (boost & coil wear)
Ignition coilsreplace as a set when misfires start (~80–100k)
Timing belt kit + water pump60–75k mi / 6 yrs
Air filter(s)15–20k mi
Coolant (G12)every 2–3 yrs
Brake fluid (DOT 4)every 2 yrs
Manual gearbox / diffs oil40–60k mi
Tiptronic ATF (01V)40–60k mi (pan + strainer)
Power-steering fluidevery 3–4 yrs
Diverter valves, hoses, clampsinspect yearly
Fuel filter30–40k mi

Service timeline

Every oil changeOil + filter, look for leaks (turbo oil lines, valve covers), check coolant level.
Every 15–20kAir filters, brake inspection, tyre rotation, charge-pipe clamps.
Every 30kSpark plugs, fuel filter, brake fluid check, PCV/breather inspect.
Every 60kTiming belt & water pump kit, drive belt, tensioner, gearbox & diff oil.
~100k+Coil packs, engine mounts, turbo health check (shaft play, smoke), suspension bushings.

11 My service tracker

Set your odometer in My car, then enter when each job was last done. The tracker shows what's due — saved automatically in this browser.

12 Fluids & consumables

Typical spec — confirm with your VIN/year in the manuals or Audi parts lookup.

ItemSpecification ≈
Engine oilFully synthetic 5W-40 to VW 502 00 / 505 00 · ≈ 4.5–5 qt (4.3–4.7 L) with filter — fill to the dipstick
CoolantG12 / G12+ (pink/purple) mixed 50/50 with distilled water
Brake / clutch fluidDOT 4, replace every 2 years
Power-steering fluidPentosin CHF 11S (VW G 004 000)
Tiptronic ATFDexron-III compatible / VW ATF G 052 025 A2 (check 37-133 PDF)
Manual gearbox & diffs75W-90 synthetic gear oil (see transmission PDFs for exact fill)
Spark plugsAudi-spec/NGK/Bosch cold-range plugs, gap ≈ 0.8 mm (check parts catalogue for your code)
FuelPremium: 91+ AKI (98 RON) — 95 RON works with less power
Tip: Don't mix coolant types and don't run straight distilled/straight coolant — the plastic coolant flanges and radiator are weak points already.

13 Symptom finder

Tap what the car is doing — get the likely causes in order of "check this first".

14 Common problems & fixes

Sorted roughly by how often they bite. Priority: fix soon watch minor

fix soon Failed diverter (recirculation) valves
Symptoms: hiss/flutter on lift-off, boost loss, hesitation. Why: original diaphragms tear with age. Fix: replace with updated metal-piston style valves (fit both). Cheap and common first upgrade.
fix soon Vacuum & boost leaks / brittle hoses
Symptoms: low boost, lean codes, rough idle, limp mode. Check: smoke test; rubber elbows/T-pieces in the "hot V", intercooler couplers, N75 vacuum lines, brake booster line. Fix: replace cracked hoses with silicone/OEM updated parts.
fix soon Overdue timing belt / tensioner
Risk: interference engine — failure destroys valves. Do: full kit every 60–75k mi (belt, tensioner, idlers, water pump, thermostat, seals). Also: check cam chain tensioners and guides.
watch Ignition coils & misfires
Symptoms: flashing CEL under boost, shuddering. Fix: swap coil to a different cylinder to see if misfire follows; replace plugs at the same time. Use quality coils (OEM/Bosch).
watch Coolant flanges & leaks
Plastic coolant flanges on the back of the engine, thermostat housing and hoses age and crack. Check for sweet smell, white crust, falling level. Replace with updated metal/aluminium flanges when accessible.
watch Turbo wear / oil supply
Symptoms: blue smoke, whine/siren noise, slow spool, oil in charge pipes. Cause: neglected oil changes, shutting off hot, clogged oil feed/return. Fix: check shaft play, rebuild/replace in pairs ideally, replace oil feed filters and lines.
minor MAF sensors (×2)
Dirty or failing sensors cause lean/rich codes and hesitation. Clean with MAF cleaner only; replace if readings are out of balance in the measuring blocks.
minor PCV / breather & oil leaks
Cracked breather hoses, valve-cover gaskets and cam-adjuster seals leak oil. Replace as a group; blocked PCV can push oil past seals.
minor Front suspension wear (B5 classic)
Four-link front axle: bushings, tie rods and wishbones wear. Clunk over bumps or vague steering = inspect control-arm bushes and track-rod ends. Manuals: Suspension, Wheel & Steering folder.

15 Diagnostics & codes

Quick reference for scan-tool work. Use a VAG-COM/OBDeleven-class tool for measuring blocks and adaptation.

CodeMeaning ≈ / first checks
P0299Underboost — leaks, diverters, N75, wastegate
P0234Overboost — N75/hoses, wastegate stuck, tune
P0243N75 wastegate solenoid circuit
P0171 / P0174Lean bank 1 / 2 — vacuum or boost leak, MAF, fuel pressure
P0101MAF plausibility — sensor dirty/faulty, intake leak
P0300–P0306Misfire (random / cyl 1–6) — plugs, coils, injectors
P0420 / P0430Cat efficiency bank 1 / 2 — old cats, O2 sensors

Useful scan-tool functions

  • Address 01 Engine → read DTCs, measuring blocks (MAF, boost actual vs specified).
  • Check specified vs actual boost under load (a data-log pull in 3rd gear).
  • Fuel trims (long-term) tell you about vacuum leaks vs fuel delivery.
  • Confirm misfire counters per cylinder.

16 Upgrades & sensible limits

What's popular on the 2.7T and where the weak links are.

Stage 1

ECU tune + metal diverters + test pipes/cat-back. Typical ≈ 300–340 hp on stock turbos. Needs healthy plugs/coils and fresh maintenance.

Stage 2 / K04

K04 turbo swap, bigger SMICs/FMIC, 440cc injectors, upgraded clutch & fueling. ≈ 350–420 hp. Boost control and cooling become critical.

Weak links

Clutch & dual-mass flywheel, 01E/Tiptronic torque tolerance, stock fuel pump, small SMICs, rubber vacuum parts. Plan drivetrain upgrades before power.

Reality check: every 20+ hp costs reliability. Fresh timing belt, healthy cooling, a wideband gauge and conservative boost are the best "mods" for longevity.

17 Parts list

Add parts as you read the manual, run a search or look up a problem — then export a shopping list. Every part can carry a part number, price, vendor, notes, and a link back to the exact manual page.

How to add parts

  • In the manual viewer: press + Add part (it links the part to that page), tap a part mentioned on the page, or add a ready-made job kit.
  • From search: searching “timing belt”, “clutch”, “heater core”… shows a Typical parts kit.
  • From problems: each fault card has a + Parts button.
  • Floating 🧰 button (bottom-left) opens your list anywhere.

Supplier catalogs

Per-part “Find” links search ECS Tuning, FCP Euro, Autohaus AZ, 034Motorsport, IND, Awesome GTI, Blauparts, RockAuto, eBay and Amazon using the part number (or name + your car). I can’t see live stock or prices — confirm fitment with your VIN before ordering.

18 Manual library — PDFs, one click

Every PDF from your Audi_A4-B5-chassis-Typ-8D-1994-2001 folder, grouped by system. Start with the S4 (APB / quattro) tab; the other engine families are kept separate so they don't clutter your searches.

Find a procedure

Browse by system

19 ID, codes & notes

Where to find codes

  • VIN: base of windscreen (driver side) & B-pillar plate.
  • Data sticker: spare-wheel well + service book (engine, gearbox, paint, option codes).
  • Engine code: front of right bank on the block (e.g. APB).

Engine-code cheat sheet

CodeMarket / year ≈Output
AGBEU, 1997–2000265 PS
ARYEU, 2000–2002265 PS
APBUS, 2000–2002 (your manual)250 hp
Your own notes: use the browser's Print → Save as PDF to take a snapshot, or add your VIN / service history below this line in the HTML file.