PRE-TUNE CHECKLIST
Run through this before tune day — mobile, drop-off, or remote. Printable.
Why this matters: calibration is not a repair. A tune can't fix a
mechanical problem — it can only hide it or make it worse. Every box you check here is time on
tune day spent tuning instead of diagnosing.
Ignition
- Spark plugs are the right heat range and gap for the combination (boosted and nitrous combos usually need a colder plug, gapped down).
- Plugs, coils, and wires are in known-good condition — no random misfires.
Fuel system
- Fuel filter is fresh (if the vehicle has a serviceable one).
- Fuel pump can support the power goal — a stock pump doesn't feed a big cam and boost.
- Injector part number / flow data is known and disclosed if not stock.
- E85 / flex-fuel: working ethanol content sensor installed and lines are ethanol-rated.
- The tank has the fuel the tune is being built for — fresh, from a good station.
Air path
- Air filter is clean; MAF sensor is clean and reading.
- No vacuum leaks — check hoses, fittings, intake gaskets.
- Boosted: clamps tight, couplers healthy, no boost leaks (pressure-test if you can).
Engine health
- No active misfires and no unresolved trouble codes — if a light is on, tell us what and why before tune day.
- Oil level correct, oil in good condition, no significant leaks.
- If there's any doubt about a cylinder, do the compression / leak-down test before scheduling.
Cooling & charging
- Coolant level correct, fans working — tuning involves repeated load pulls at operating temperature.
- Battery healthy and charging system working. Flashing a module with weak voltage can brick it; remote customers should keep a maintainer on the battery during writes.
Drivetrain
- Transmission fluid level and condition good — required if transmission calibration is part of the job.
- Tires in safe condition and properly inflated (they carry the load testing).
- No driveline vibrations or slipping that "only happens sometimes." Tell us about it.
Tune day (mobile / drop-off)
- At least half a tank of the agreed fuel.
- Any parts going on the vehicle are ON the vehicle — tune day is not install day.
- Plan for the session: drop-off runs are typically 4-5 hours.
Found a problem going through this list? That's the checklist working — tell us and we'll figure out the order of operations together. Diagnostics is a service we offer too.