VAGPULSE  ›  The Tuning Bible  ›  Tuning Dictionary - Every Term, In Plain English
13

The Map
Dictionary

Bosch named every map in German, abbreviated it, and never explained it. This is the translation — what each one does, in the order you'll actually meet them.

Part 13 · The Map DictionaryThe Tuning Bible
Chapter 13.1

The maps you will actually touch

EVERY MAP BELONGS TO ONE OF FOUR JOBS AIR how much gets in KFMIRL LDRXN KFLDRL KFLDIMX how much air to ask for the ceiling on that ask wastegate pre-control the PID's limit FUEL matching it exactly LAMFA MLHFM KRKTE KFLBTS how rich at full throttle what the MAF is telling us how big the injectors are extra fuel to cool parts SPARK when to light it KFZW KFZW2 KFZWOP KFTSRL base timing timing with cams moved the ideal, before knock coil charge time LIMITS the hard stops KFMIOP NMAX VMAX KFLDHBN most torque allowed rev limiter speed limiter max turbo pressure ratio THESE FOUR MOVE TOGETHER — THAT IS THE WHOLE CRAFT More AIR needs more FUEL, and more of both needs less SPARK. Any LIMIT left where it was will clip all three. Where a Stage 1 lives: KFMIRL and LDRXN (more air), KFZW (protect it), LAMFA (feed it), KFMIOP (let it through). What you rarely touch: MLHFM and KRKTE — only when the MAF housing or the injectors physically changed.

There are hundreds of maps in an ECU. On a normal Stage tune you meet about eight. Learn these and the rest are context.

MapGerman it comes fromWhat it doesTurn it up and…
KFMIRLKennfeld Motor-Ist zu Rel. Last Requested torque → requested load. The main power dial. The engine asks for more air. Everything else must keep up.
LDRXNLadedruck-Regelung, max The boost ceiling by rpm More boost is permitted — if the turbo can make it.
KFLDRLKennfeld Ladedruck-Regler Boost controller duty — how hard the wastegate is held shut Boost arrives faster; overshoot if too aggressive.
KFZWKennfeld Zündwinkel Ignition timing advance More torque — until it knocks. The most dangerous map in the file.
LAMFALambda Fahrer-Anforderung Target mixture under load Richer = cooler and safer; too rich = power and plugs suffer.
KRKTEKraftstoff-Konstante Injector constant — how much fuel one injector delivers Only change it when the injectors themselves change.
MLHFMMassenluft Heissfilm-Messer MAF scaling — airflow sensor calibration Wrong here and every fuelling decision downstream is wrong.
KFMIOPKennfeld Motor-Ist Optimal The engine's torque ceiling model Left too low, it quietly caps everything you did in KFMIRL.
🔑 The order they work in

KFMIRL decides how much torque you want → LDRXN / KFLDRL get the air to make it → KRKTE / LAMFA / MLHFM put the right fuel with it → KFZW lights it at the right moment → KFMIOP is the ceiling the whole thing is measured against. Change one without the others and the ECU simply corrects you back.

Part 13 · The Map DictionaryThe Tuning Bible
Chapter 13.2

The supporting cast

You will see these referenced in forum threads and definition files. You rarely edit them, but knowing what they are stops a lot of confusion.

Limiters & protection
LDRXNZK — boost limit under knock
NMAX — rev limiter
VMAX — speed limiter
KFDLBTS — hot-weather / heat protection pull
These exist to save the engine. Raising them removes a safety net, not a restriction.
Fuelling detail
LAMFAW — warm-up mixture
KFLF — load correction factor
FKKVS — injector correction
KFPED — pedal → requested torque
KFPED is the one people mistake for a power map — it changes how the pedal feels, not what the engine can make.
Diesel-specific
IQ / MENGE — injection quantity
SOI — start of injection (diesel's "timing")
LDR — boost control
SMOKE — smoke limiter, fuel vs measured air
On a TDI the smoke limiter is the real ceiling: add fuel past it and you make soot, EGT and a DPF problem, not power.
Checksums & structure
CRC / sum16 — integrity checks
RSA block — signed code area (later ME7.1.1)
Edit a map and the checksums no longer match; the ECU may refuse the file or run in limp. Any competent tool corrects them automatically — VAGPULSE does it and verifies before anything is written.
⚠ Names vary between families

These names come from the ME7 world and carry over loosely to MED9/MED17. On Simos and EDC17 the same ideas exist under different labels. Always work from a definition matched to your actual file, never from a name you recognised in a forum post.

Part 13 · The Map DictionaryThe Tuning Bible

Read it, then do it

Everything in this chapter is something VAGPULSE does on a real car: read the ECU over OBD, see these same maps by name, and flash a checked file back with your original saved first.

See VAGPULSE