928 S4/GT/GTS (1987-1995)

Individualized performance for your S4, GT, or GTS!
Automatically creates a custom advance map for EACH cylinder
Each cylinder is optimized for its own unique airflow and knock tolerances
More power across the rpm range at rpms not available when manual tuning

DIY option: replaces base map with your custom tuned file (EG. cam swap, turbo, SC)

EZK new code highlights:
- 8 learned maps, 1 for each cylinder
- Soft rev limit, ignition retard (6400)
- Knock light/CEL enabled
- Diagnostic flashing

- New knock sensors
- New CPS (crank position sensor)
- New TPS (throttle position switch)
- New Hall sensor (cam position)

Recommended octane:
S4.....91 US/AKI (95 EU/RON)
GT....91 US/AKI (95 EU/RON)
GTS..93 US/AKI (98 EU/RON)

- EZK-S chip
- case label
- PKStick'r

Buy It! (in stock)

Installation instructions (Mike Benno) - EZK Self Tuning Chip Installation


Q: What does EZK-S stand for?
A: Elektronische Zündung mit Klopfsteuerung - Selbstlernende/Selbstoptimierende
A: Electronic Ignition with Knock-control - Self-learning/Self-optimizing

Q: How long does it take the EZK-S chip to generate new maps?
A: About an hour for the initial learning, the entire map is filled in about four hours of driving

Q: Why a maximum of 93 AKI octane?
A: S4-up 928s were designed when premum unleaded was not available in ultra-high octane
A: Very high octane may actually decrease performance with the EZK-S

Q: What gains are to be expected for a S4/GT/GTS with stock exhaust?
A: If there is better performance to be gained with ignition advance the chip should find it
A: Most people report much better response at a minimum

Q: How and when should I reset the learning?
A: Hold pedal to floor, turn key to ON, seasonally or when going up in fuel octane rating
A: From v2.2, automatic partial reset on cold start limits excessive per cylinder retard

Q: How does it drive while the EZK-S is learning?
A: May feel flat at certain RPMs but becoming smoother and more powerful over time

Q: Why does the exhaust sound different?
A: As ignition timing is optimized more power goes to the wheels vs. wasted as noise

Q: What is a soft rev limit?
A: At the soft limit power is reduced so that the hard fuel cutoff cannot be reached

Q: Where is the CEL?
A: 91-95 have a Check Engine Light, 89-90 need a bulb installed (red B8.4D)
A: 87-88 can wire a 12V bulb/LED to the diagnostic plug

Q: What information will the CEL show?
A: Knocks, knock and hall sensor errors, and if the learning has been reset
A: From v2.4, 1 flash at idle = bad front knock sensor, 2 flashes = rear KS, 3 = Hall sensor

Example of four cylinders versus stock timing after a couple of hours of driving