Mechanical issues are the most common reasons for unsatisfactory tuning results. However, they can be easily identified and rectified before the tuning session.
Therefore, we will share a Dyno Tuning checklist below to help you make sure your vehicle and engine are in perfect condition before your tuning session, and the dyno tuning cost is under your control.
Mechanical Engine Health
You need to ensure that you are tuning a healthy engine. Finish a compression test and a cylinder leak-down test before your tuning appointment.
Perform the compression test on a warm engine. The fuel injectors should be unplugged, and the throttle should be held fully open while testing. Expect the pressure valves to be more miniature when the elevations are high and lower on engines with more mileage.
Make sure there is not more than 20psi variance between cylinders. If you find one cylinder displaying a more significant variance than 20psi, then repair the mechanical problem first before your dyno tuning appointment. You will realize the additional cylinder pressure after a custom tune. It will only exploit the current mechanical issue causing further and usually more severe engine failure.
You can also perform a cylinder leak-down test on a warm engine. However, make sure the cylinder leakage is not more than 18-20% in any cylinder.
And if you do, you have to test further to evaluate if the air is leaking from and to; head gasket, intake valve seat, piston rings, exhaust valve seat, etc.
However, do note that even if the test results appear promising, you may still have mechanical damage in your engine. Therefore, take a help of a specialist who can easily recognize any negative symptoms and inform you about the consequences of further turning your engine if they identify any issues.
Do not forget to check for engine oil, other lubrication, or fluid leaks. Make sure you use the proper turbo oil feed and return lines and that they are correctly installed. Remember, any fluid or oil leak can worsen if the drivetrain or engine is warmed up while on the dyno.
Make sure the engine oil’s lubrication is appropriately sealed to ensure dyno tuning continues safely.
Charge Pipe/Intercooler System, Intake, Turbo, and Vacuum Line Integrity
Do not forget to clean the intake filters properly. Do it before a dyno tuning session. The last thing you want is something as small as a clogged intake filter impacting power production.
Pressure, vacuum, or smoke check charge intercooler/pipe, all intake, and vacuum lines. Ensure that your vacuum lines, intercooler piping, and your intake are sealed when pressurized, like when running a full boost.
Also, ensure all intercooler piping and vacuum lines are secure, so they don’t blow off at the tuning appointment.
Check the entire exhaust system. Tighten all the bolts, especially the exhaust system bolts or nuts. An exhaust leak before the turbo will lose power and make part throttle tuning impossible. An exhaust leak in the exhaust system before the WBO2 sensor can also mess up the sensor accuracy.
Also, make sure the BOV is sealing correctly. The blow-off valve should be adequately lubricated, seals tight, and function properly.
Do a test for excessive turbo shaft play. Make sure the turbo wheels do not spin. Also, see if your fingers reach into the inlet side of the compressor, and you can grasp the shaft. Try to move the shaft up and down, left and right.
Do you see the shaft moves seamlessly in these directions?
That means your turbo has excessive shaft play. Your turbo won’t work correctly if it worms excessively. So either rebuild the turbo or purchase a new one.
General Pre-Tuning Maintenance Checklist
Below are some key points that should be part of your dyno tuning checklist to control the dyno tuning cost.
● Your fluid levels should be where they need to be.
● Your Check Engine Lights (CEL), Codes, or Malfunction Indicator Lamps (MIL) shouldn’t be on.
● The fuel injectors should be cleaned and checked for a system balance in regular intervals.
● Replace old fuel filters.
● Replace your old spark plugs
● Make sure the wheels and balanced and aligned.
● The vehicle must be steerable, and the driveline and drivetrain systems must be intact and safe.