Can OBD2 Calculate Engine Torque? Yes, With Limits 

That distinction matters. A scanner that shows a torque number is not always measuring twisting force at the crankshaft. In most cases, it is showing a value the engine control unit has modelled, or a figure an app has estimated from other live data. Knowing which kind you are looking at tells you how much to trust it.

How OBD2 Reports Torque

Generic OBD2 live data is organised into Modes and Parameter IDs, or PIDs. Mode 01 shows current data, and three PIDs in that mode are the key to torque. They do not work on every vehicle, and support must be checked rather than assumed.

The percentage PIDs are the part most readers miss. PID 0x62 does not say “200 Nm.” It says, in effect, “the engine is producing this percentage of its reference torque.” PID 0x61 is different again: it reflects what the driver is asking for through the accelerator, not what the engine is actually delivering at that moment. A gap between the two can be normal during a gear change or traction control intervention.

PID 0x63 supplies the scale. Reference torque is a fixed value for that engine, expressed in newton-metres, against which the percentages are measured. Without it, a percentage alone cannot be turned into a newton-metre figure. The OBD-II PID list sets out these Mode 01 definitions, including PIDs 0x61, 0x62, and 0x63.

How to Turn Percent Torque Into Newton-Metres

The conversion is simple once both values are present. Multiply the reference torque by the actual torque percentage, then divide by 100.

Actual torque (Nm) = reference torque (Nm) × actual percent torque ÷ 100

For example, if reference torque is 400 Nm and PID 0x62 reports 50%, the estimate is 400 × 50 ÷ 100, or 200 Nm. If the same engine later reports 80%, the estimate becomes 320 Nm. The maths is not the hard part. Getting both PIDs from the same vehicle, at the same moment, is.

That is also why a torque reading should be treated as a snapshot, not a specification. It changes with throttle, engine speed, gear, temperature, and load. A single value at idle says little about peak torque.

What If Your Car Does Not Support the Torque PIDs?

Many vehicles do not. Manufacturers are not required to support every Mode 01 PID, and support varies by make, model, year, and engine type. They tend to appear more often on heavier-duty and some diesel applications than on every small petrol car, but that is a tendency, not a rule for a particular vehicle.

The practical check is to look at the supported-PID list. PID 0x60 reports which PIDs from 0x61 to 0x80 are supported. A capable scanner or app should show whether 0x61, 0x62, and 0x63 are present. If they are absent, a generic scan will not produce a trustworthy torque figure, however good the adapter is.

Manufacturer-specific, or enhanced, PIDs are a separate route. Some makes expose their own torque values outside the generic set, and some professional or brand-specific tools can read them. Those values still come from the manufacturer’s own model, and they are not interchangeable with the generic PIDs.

How Apps Estimate Torque Without Those PIDs

When the torque PIDs are missing, many phone apps still display a torque or horsepower gauge. That figure is usually estimated, not read directly. The app may work backwards from power and engine speed, using the relationship between power, torque, and revolutions per minute.

In imperial units, the familiar form is: horsepower = torque in pound-feet × RPM ÷ 5,252. Rearranged, torque = horsepower × 5,252 ÷ RPM. In metric units, power in watts = torque in newton-metres × angular speed in radians per second, where angular speed = RPM × 2π ÷ 60.

That route has a weakness: it needs a reliable power figure first. Some apps estimate power from acceleration and vehicle weight, or from airflow and fuel data. Vehicle weight, gradient, wind, and drivetrain losses all affect that estimate, so a small error in weight or acceleration can produce a noticeably wrong torque number.

This is also where engine load is easily confused with torque. Calculated engine load, PID 0x04, is a percentage that describes how hard the engine is working relative to its capacity. It is useful context for a torque reading, but it is not torque, and it cannot be converted into newton-metres on its own.

Engine Torque, Wheel Torque, and Power Are Not the Same

Engine torque is the twisting force at the crankshaft. Wheel torque is what reaches the driven wheels after the gearbox and final drive have multiplied it, minus drivetrain losses. That is why first gear feels so much stronger than top gear even though the engine itself has not changed: the gear ratio has changed the torque at the wheels.

Power is a third quantity. It combines torque and speed. An engine can produce high torque at low RPM and still produce modest power, or produce the same torque at higher RPM and produce much more power. Comparing torque with horsepower without stating RPM is therefore incomplete.

For a diagnostic check, engine torque is usually the more useful number, because it stays closer to what the engine control unit is modelling. Wheel torque is more relevant to acceleration feel, but it requires gear ratio and loss assumptions that a generic OBD2 scan does not supply.

Why an OBD2 Torque Reading Is an Estimate, Not a Dyno Result

Most road cars do not have a torque sensor on the crankshaft measuring twisting force directly. The engine control unit instead models torque from inputs such as airflow, fuel delivery, engine speed, throttle position, and ignition or injection timing. That model is good enough for engine management, but it is still a model.

Several factors can shift it. Sensor drift, a modified intake or exhaust, a remap, a faulty airflow sensor, or a change in fuel quality can all move the modelled value away from the true output. Sampling rate matters too: a cheap adapter updating once or twice a second can miss a brief peak or show a lagging value during rapid acceleration. That does not make the reading useless, but it does make it unsuitable as proof of a claimed power gain.

A chassis dynamometer measures output at the wheels under controlled conditions, with its own corrections and losses. An OBD2 estimate and a dyno result can therefore differ honestly: they measure related but different things, by different methods. For more on live-reading trust, see our guide to how accurate OBD2 live data is.

How to Check Torque Sensibly on Your Car

Use a short, repeatable routine rather than chasing a single peak number.

1. Connect with the engine running and check whether PIDs 0x61, 0x62, and 0x63 are supported. If they are not, note that before trusting any app gauge.
2. Record reference torque first, then watch actual percent torque at idle, at a steady cruise, and under a brief, safe increase in throttle.
3. Convert the percentages yourself using the formula above, so you can see whether the app’s newton-metre figure matches the raw PIDs.
4. Compare the result with what the RPM PID shows at the same moment, because torque without RPM gives an incomplete picture of power.
5. Repeat the check under similar conditions if you want to compare before and after a change. A single run on a different road, in different weather, is not a fair comparison.

If torque stays at zero, stays fixed while throttle changes, or jumps wildly, suspect missing PID support, an app estimate, or a communication problem rather than a sudden engine fault. Cross-check with what OBD2 live data can show and with which OBD2 PIDs are most useful before drawing a conclusion about the engine itself.

Frequently Asked Questions

Does every car show engine torque through OBD2?

No. Torque PIDs 0x61, 0x62, and 0x63 are part of the generic Mode 01 set, but manufacturers do not have to support every PID. Check PID 0x60 support first. If those PIDs are absent, a generic scanner cannot report torque directly, even if an app still displays an estimated gauge.

What is engine reference torque?

Reference torque, PID 0x63, is a fixed newton-metre value for that engine against which percentage torque is measured. Actual torque in newton-metres is reference torque multiplied by actual percent torque and divided by 100. Without reference torque, a percentage cannot be converted into newton-metres.

Can OBD2 show torque in pound-feet?

Yes, by conversion, once you have a newton-metre figure. One newton-metre equals about 0.738 pound-feet, so 200 Nm is about 148 lb-ft. Convert after calculating the newton-metre value, rather than mixing units partway through the calculation.

Why does my app show torque but my scanner does not?

The app is probably estimating torque from power, RPM, acceleration, or vehicle weight, while the scanner is showing only PIDs the vehicle actually supports. That difference is common. Check whether the app names a PID; if it does not, treat its figure as an estimate.

Is OBD2 torque accurate enough for tuning?

It is useful for spotting trends and comparing runs under similar conditions, but it is not a substitute for a dynamometer measurement. Modelled torque can shift with sensor condition, modifications, and sampling rate, so small claimed gains from OBD2 alone should be treated with caution.

Can OBD2 calculate wheel torque?

Not directly from generic PIDs. Wheel torque depends on engine torque, the current gear ratio, the final drive ratio, and drivetrain losses. A generic scan does not supply all of those values, so any wheel-torque figure is an estimate built on extra assumptions.

Conclusion

OBD2 can calculate engine torque, but only in the two-part sense that matters for a real car: a percentage from PID 0x62, scaled by the reference torque in PID 0x63. When both are supported, the conversion is straightforward and the result is a useful modelled estimate. When they are not, an app gauge is an estimate built on other assumptions, not a direct reading. Check PID support first, log the raw values, and use the figure for trends and sensible checks rather than as a dyno result.