P0411 / P0441 misfire after an SAI or purge delete | 46 — Secondary Air Injection | 7 — DFPM & Emissions Strategy |
P0420 catalyst efficiency | 52 — Rear O2 & Catalyst | 50 — Misfire Detection |
P1556 / P1557 boost deviation | 17 — Boost Control & LDR PID | 48 — Altitude & Turbo Protection |
VCDS connects but the engine will not crank | 10 — Serial EEPROM & Immo | 36 — Engine Speed Sensing |
| Boost does not reach target | 17 — Boost Control & LDR PID | 38 — External Wastegates |
| Building a datalog definition | 12 — RAM Logging & .ecu Files | 35 — High-Speed Logging |
| Building a track harness | 39 — Harness Fabrication | 13 — 121-Pin Harness |
| Converting a longitudinal donor to transverse | 9 — Donor ECU Conversion | 5 — Cross-Flash Clusters |
| Dead output driver on the board | 34 — PCB Repair & IC Pinouts | 13 — 121-Pin Harness |
DTC P0601 memory checksum error | 11 — Flash Checksum Hierarchy | 6 — Memory Geometry & Axes |
| Electronic throttle limp mode, 1500 rpm limit | 22 — E-Gas Throttle Control | 16 — Torque Model & Inversion |
| Engine runs but the CEL is on after flashing | 11 — Flash Checksum Hierarchy | 25 — Troubleshooting & Failsafes |
| Ethanol / E85 fuelling | 24 — Flex-Fuel / Ethanol | 21 — Cold Start Enrichment |
| EVAP leak-detection pump DTC | 28 — EVAP & Leak Detection Pump | 49 — Tank Ventilation (N80) |
| False knock on forged pistons or solid mounts | 37 — Knock Sensor Recalibration | 18 — Knock Control & BTS |
| Going lean above 6000 rpm | 56 — Fuel Pumps & Rail Pressure | 15 — Injector Mathematics |
| Going to speed density / MAFless | 31 — MAFless / Speed Density | 22 — E-Gas Throttle Control |
| Idle hunt with a high-lift cam | 41 — Idle Speed Control | 44 — High-Lift Camshafts |
| Immobiliser light on, engine blocked | 10 — Serial EEPROM & Immo | 25 — Troubleshooting & Failsafes |
| Injector not delivering full flow | 15 — Injector Mathematics | 56 — Fuel Pumps & Rail Pressure |
| Jerk on tip-in or lift-off | 32 — Anti-Jerk Damping | 42 — Wall Wetting & Transients |
| Knock at high load | 18 — Knock Control & BTS | 37 — Knock Sensor Recalibration |
| Logging faster than 4 channels | 35 — High-Speed Logging | 12 — RAM Logging & .ecu Files |
| Long-term fuel trim will not settle | 60 — Post-Dyno Verification | 49 — Tank Ventilation (N80) |
| Misfire only with a lightweight flywheel | 50 — Misfire Detection | 32 — Anti-Jerk Damping |
| N249 diverter blowback | 27 — Diverter Valve N249 | 7 — DFPM & Emissions Strategy |
Rough running / P0300 | 50 — Misfire Detection | 29 — Dwell & Ignition Coils |
| Rpm limiter hits early or never | 14 — Code Hooks & Patching | 54 — Launch Control & Anti-Lag |
| Rpm will not read on the logger | 36 — Engine Speed Sensing | 12 — RAM Logging & .ecu Files |
| Sign-off before the first drive | 60 — Post-Dyno Verification | 25 — Troubleshooting & Failsafes |
| The ECU will not talk on the K-line | 20 — Bench Flashing & BSL | 25 — Troubleshooting & Failsafes |
| Timing won't advance on an aftermarket cam | 44 — High-Lift Camshafts | 19 — VVT Cam Phasing |
| Turbine or exhaust valve running hot | 51 — EGT Model & Component Protection | 48 — Altitude & Turbo Protection |
| Turbo overspeed on a big turbo | 48 — Altitude & Turbo Protection | 51 — EGT Model & Component Protection |
| Upgrading the throttle body | 22 — E-Gas Throttle Control | 43 — Intake Resonance (SRU) |
| Want a 2-step or rolling launch | 54 — Launch Control & Anti-Lag | 14 — Code Hooks & Patching |
| Want water-meth injection | 30 — Water-Methanol Injection | 14 — Code Hooks & Patching |
| Which donor file will flash into my ECU | 4 — DAMOS-to-ECU Matrix | 5 — Cross-Flash Clusters |
Wideband goes lean / P0130 | 26 — Wideband O2 & CJ125 | 51 — EGT Model & Component Protection |