EQT Tune Reliability Claim Evaluated


Following on the heels of my post about Ed Susman from Equilibrium Tuning bullshitting a consumer, the business began advertising a claim that is worthy of inclusion in my Top 5 – Dubious Product Claims list.

This latest advertisement addresses a common concern about the potential detrimental effects of using an aftermarket engine tune on vehicle reliability.

Reliability is defined as the probability that a product, system, or service will perform its intended function adequately for a specified period of time, or will operate in a defined environment without failure.

American Society for Quality (ASQ)

EQT claims to address reliability concerns by selling modified engine software that they claim does not affect reliability.

Our power delivery combined with OEM-like (sic) drivability and reliability is what…

Equilibrium Tuning Inc. Product Performance Claim
EQT Reliability Claim
EQT Reliability Claim

Claim Validity:

The claim of OEM-like reliability is doubtful for several reasons.

The first is that EQT increases the operating boost pressure of its IS20 Stage 2 tune well above the OEM level, shown in a comparison in the chart:

EQT vs OEM Boost Pressure
EQT vs OEM Boost Pressure

This increase is expressed as a percentage above the OEM level in the next chart, starting around 30% and climbing to 75% more boost pressure:

EQT Boost Pressure Increase Versus OEM
EQT Boost Pressure Increase Versus OEM

EQT is asking consumers to believe that even though they are increasing the pressure and temperature stresses on the engine components, the failure rate and time to failure of those products is unaffected by the increased stressors.

EQT’s marketing people seem to be taking P.T. Barnum’s view:

Many people are gullible, and we can expect this to continue. - P. T. Barnum

Note: You may wonder if EQT might operate at lower timing than stock, no, EQT operates with more ignition timing too – causing even greater pressure and temperature.

EQT vs OEM Ignition Timing
EQT vs OEM Ignition Timing

The second reason EQT’s claim of having OEM-like reliability is doubtful is because EQT significantly raises the Knock Threshold.

The Knock Threshold is the safety margin that once surpassed leads to the ECU intervening to protect the engine from the damaging effects of knock. (This is discussed in more detail on the Noise and Knock page)

Shown in the next charts is how much looser EQTs safety margins are compared to the OEM software:

Note: OEM is the baseline; 0% deviation from itself.

EQT Cylinder 1 Knock Threshold Increase vs OEM
EQT Cylinder 1 Knock Threshold Increase vs OEM
EQT Cylinder 2 Knock Threshold Increase vs OEM
EQT Cylinder 2 Knock Threshold Increase vs OEM
EQT Cylinder 3 Knock Threshold Increase vs OEM
EQT Cylinder 3 Knock Threshold Increase vs OEM
EQT Cylinder 4 Knock Threshold Increase vs OEM
EQT Cylinder 4 Knock Threshold Increase vs OEM

With ECU software changes that raise the Knock Threshold compared to OEM by 100% and more, reducing the probability that the ECU will intervene during a potential Knock Event, EQT wants consumers to believe that this will not affect the long-term failure rate and time to failure of an engine.

Here again, EQT marketing …

There is a fool born every minute - P. T. Barnum


Equilibrium Tuning conducts business in the United States and is subject to advertising and marketing laws enforced by the Federal Trade Commission.

Concerning product performance claims, the Federal Trade Commission has this to say about what is required from businesses:

It is an unfair or deceptive act or practice for an advertiser to make an objective product claim without having a reasonable basis, at the time the claim is made, consisting of competent and reliable evidence.

Federal Trade Commission Act – Section 5(a)(1)

By law, EQT must have competent and reliable evidence that substantiates its claims about the reliability of its software compared to OEM software.

On June 17, 2024, I reached out to EQT to learn how they are substantiating their claim:

Thus far EQT has failed to even respond to the inquiry let alone adequately address the unsubstantiated product claim.

In the past, I made a post discussing the topic of determining product reliability. It was pointed out that conducting root cause analysis can be very complicated, involving a vast amount of data collection and review to produce reliability metrics.

As astounding as it would be for EQT to have collected the amount of data needed to substantiate this claim, the fact that many of the vehicles are still in service means that failure rates and mean times to failure are changing daily as the vehicles continue to operate.

For EQT to claim their tune is as reliable as OEM they would need to have conducted Accelerated Life Testing on a large number of vehicles, using multiple versions of their software, as well as OEM software.

Accelerated life tests are component life tests with components operated at high stresses and failure data observed.

National Institute of Standards and Technology (NIST)

EQT Damages:

Absent a reasonable basis Equilibrium Tuning’s claim constitutes an unlawful and deceptive business practice.

Equilibrium Tuning has the potential to harm consumers by misleading them about the reliability of its software compared to OEM software which may affect consumers’ behavior or decisions about the product or service.

The Equilibrium Tuning claim also harms other businesses that use ethical advertising, potentially depriving those ethical businesses of sales if consumers are misled into believing EQTs ECU tune is more reliable.


Failing to have a reasonable basis at the time the claim was made, consisting of competent and reliable evidence, would mean the business is engaging in an unfair or deceptive act or practice.

EQT provides no accompanying substantiation for the product performance claim, and the business has failed to respond to the request I made for substantiation.

Businesses that use unfair or deceptive acts or practices in advertising can harm consumers and also businesses that are acting ethically.


8 thoughts on “EQT Tune Reliability Claim Evaluated”

  1. My engine popped on their 91 is38 tune at 2500 rpm under low load running 93 fuel. So at that rpm under the load that the engine was under it leads me to believe that due to the knock sensor threshold increase it caused the rings in the number one cylinder to fail.

    1. Jeffrey Jones

      The subject of what potential causes are considered when a problem arises is something that I intend to address at some point.
      EQT Tuned Broken Car

  2. If you word it: “our power delivery combined with reliability and oem like driveability “ the situation changes from the assumption that statement claims oem like reliability. I’ve always been under the assumption with all my tunes that I’m part of the halt/hass program. Moreover, I still don’t understand how a tuner changes many parameters but leaves knock prevention alone. That doesn’t seem right to me. It seems more correct that if you increase pressures and timing that you also decrease the sensitivity.

    1. Jeffrey Jones

      Yes, how advertising is worded can lead to conveying different messages.

      Trying to increase power output while retaining reliability is an engineering problem. It’s not an easy problem, which requires time and effort and money to come up with a solution. A shortcut is to raise the Knock Threshold to get more power while adding risk and relying on the fact that the engine logging device (Cobb Accessport) cannot provide information to consumers that the risks to their engines have been increased.

      The page on Noise & Knock shows the linear equation from the FR that is used to calculate the Knock Threshold. If the sensitivity is decreased then the average noise level would go down, but since that is multiplied by a gain factor, the threshold would be lowered too. By increasing the gain value, the threshold can be increased while leaving the sensor sensitivity unchanged. I chose to report the knock threshold changes as a percentage difference versus the OEM level to be able to capture both potential ways of altering the knock response. It’s like using AFR, which is a metric comprised of two variables.

  3. On the knock threshold, I understand they are raised on the sneaky and EQT and somehow that’s implied to be detrimental to reliability. But so is raising boost and timing as described here, which all the tunes do. It’s too bad their cannot be a way to compare KR on the AP in an apples to apples comparison. I still am curious and uneducated in why a tuner would modify a bunch of variables around fueling, boost, and timing, and then not touch knock strategy which I’d have to imagine is related to the altered variables. Ever find out why stratified did not? – is there a reason or is it fear, lack of understanding, limited R&D, or a comprehensive understanding it is best to leave it alone?

    On the words, we have to understand what OEM-like is. Even with MTBF data on the engine, what is OEM-like? 5% from the mean on the OEM? 30%? What if there was MTBF or reliability data available? is 30% from the OEM mean/median OEM-like?

    Then – what’s driveability? the abilty for us to drive the car? The car’s ability to drive? what characteristics are these? Don’t get me started on the tune is “smoother” – I have no idea what that means. Are the RPMs jumping around? is the dyno graph line smoother?

    1. Jeffrey Jones

      Raising the knock threshold means a greater amount of knock energy, generated by increased pressure and temperature, will be present when the threshold is surpassed. Since the knock control system is reactive, not preventative, something will happen that has an effect on the system, before the system responds. It is the cumulative effect that will be a detriment to reliability.

      Yes, the fact the AP doesn’t report the knock variables is unfortunate. If I were tuning (which I am not a tuner), I’d want to maintain as much safety that the OEM built as I could. Do you think any of the tuners have the resources that VW does?

      If you look at the Stratified Revised tune results, even retaining the OEM knock thresholds they were able to make good power.

      As I mentioned in the other comment, increasing power and maintaining reliability are competing goals and the impressive accomplishment is increasing power while retaining safety features.

      The questions about what OEM-like means would be for EQT to answer. I imagine you’re putting much more thought into what that means than they did.

  4. I can’t speculate would VW would do with knock threshold with their resources at these boost levels and timing. It could look like strat, Eqt, oem, or even further reduced. I’m ignorant in this topic and still don’t know what’s correct, overly conservative, or wrong all over the place.

    Oem-like reliability is undefined and agree only EQT can say what they meant by that. We’re two Jeff’s putting a lot of thought into it 🙂

    Thanks for blog and data!

    1. Jeffrey Jones

      Determining the correct settings is mentioned briefly on the Noise & Knock page, “As the Simos 18 Funktionsrahmen explains, the process for establishing the knock sensor signal acquisition involves calibration on an engine testbench using cylinder pressure sensors to verify the correlation between knock events and overpressure for all engine operating points.

Leave a Reply