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A KARNATAKA PETROL INVESTIGATION

E20 or E31?

What’s really in your petrol? One pump label. Two competing claims. A motorist wants answers.

Everyday IndiaKarnatakaFuel & factsInvestigation

Zappy
Full-tank detective

Prof. Bolt
Evidence inspector

PART 1 · FULL TANK. OPEN QUESTIONS.

Zappy opens a petrol detective agency. The first customer is his own scooter.

EP 1

The fuel wants a lawyer

ZappyFull tank, please. And a certificate explaining everything inside it.

Prof. BoltShall we read the label before demanding its autobiography?

FILL IN!

The case begins

Karnataka says tests found ethanol reaching 31.2% in a petrol sample. Oil companies dispute the testing and say their E20 fuel meets the standard. [1] [2]

ZappyTwo claims. One confused scooter.

Prof. BoltThen our agency needs evidence before a verdict.

ZappyFine. The magnifying glass can wait beside the receipt.

A disputed result deserves investigation. It does not establish what is in every tank.

EP 2

E20 is not an exam score

ZappyDid petrol score twenty out of a hundred?

Prof. BoltThe E refers to ethanol. The number describes the blend.

Read the blend

E20 means nominally 20% ethanol by volume. Think of twenty parts ethanol in a hundred parts of finished fuel—not twenty parts added to a hundred parts petrol. [3]

Yellow: ethanol 20% · Blue: petrol 80%

ZappyA fuel recipe, then. Not its marks card.

Prof. BoltExactly. The specification also governs quality beyond the blend number.

This diagram explains the nominal blend. It is not a measurement of fuel from a pump.

EP 3

A sample grows into a rumour

ZappyOne result says 31.2. Shall I warn everyone that all petrol is E31?

Prof. BoltThat conclusion has travelled farther than the sample.

What Karnataka reported

The State’s allegation concerns sampled fuel. Reporting describes a maximum of 31.2%; it does not establish a statewide average or a result for your particular outlet. [1]

ZappyThe headline needs its sample label attached.

Prof. BoltYes. Where, when and how a sample was collected all matter.

A maximum result is neither an average nor a survey of every petrol pump.

EP 4

The other side of the counter

ZappyThe oil companies deny it. Does that erase the report?

Prof. BoltA response belongs in the file. It is not an eraser.

What the companies say

Indian Oil, BPCL and HPCL say their E20 petrol complies with IS 17021, the Indian specification, and challenge the sampling and testing procedures used. [2]

ZappySo both statements need checking.

Prof. BoltCorrect. We need the underlying records, not a contest in confidence.

An allegation is not a settled finding. A denial is not independent verification either.

PART 2 · THE DEEP DIVE

Follow the sample, the energy and the vehicle—not just the loudest claim.

EP 5

Who babysat the bottle?

ZappyPetrol enters a bottle. Bottle enters a laboratory. Mystery solved?

Prof. BoltWho collected it, sealed it and kept track of it?

The sample has a journey

A useful investigation traces collection → identification → sealing → storage → laboratory receipt. This documented journey helps establish that the tested material is the sample in question.

ZappyEven the bottle needs an attendance register.

Prof. BoltThe companies’ procedural objection makes those records important in this case. [2]

Ask for the sampling record and test report together. One cannot explain the entire process alone.

EP 6

Credentials meet questions

ZappyThe laboratory has credentials. Surely that closes every question?

Prof. BoltCredentials matter. So do the method and the sample.

Read beyond the letterhead

Ask what was measured, which method was used, whether it suits the sample and how the result was reported. Where available, examine repeat results and measurement uncertainty—the range of doubt around a result.

ZappyI had planned to stop at the impressive stamp.

Prof. BoltA credible review checks both the measurement and what the sample represents.

These are our evidence-review questions. They do not declare either side’s testing valid or invalid.

EP 7

Petrol takes up farming

ZappyWhy does fuel suddenly have an agricultural department?

Prof. BoltEthanol can be produced from crops and other plant material.

Why blend at all?

India’s programme aims to substitute some imported oil with domestically produced fuel and support the rural economy. Those are policy goals, distinct from checking a particular batch. [4]

ZappyThe programme’s purpose and the pump’s contents are separate files.

Prof. BoltExactly. Good intentions do not replace quality checks. A disputed batch does not settle every policy question.

Discuss the policy’s goals and fuel compliance separately. Both deserve evidence.

EP 8

The mileage mystery

ZappyMy mileage fell. The fuel is guilty!

Prof. BoltTraffic, tyre pressure and your enthusiastic acceleration request a hearing.

Energy is part of the story

Ethanol contains less energy per litre than petrol. Increasing its share lowers the blend’s energy per litre. Actual mileage also depends on the engine, its tuning and driving conditions. [5]

ZappySo one tank cannot diagnose the chemistry.

Prof. BoltRight. The energy effect is real; one universal mileage-loss number would be misleading.

A mileage complaint is worth investigating. It is not an ethanol-percentage test.

PART 3 · YOUR VEHICLE JOINS THE CASE

The neighbour, the handbook and a calculator with too much confidence.

EP 9

Your neighbour is not a manual

ZappyMy neighbour’s car is fine. Mine must be fine too?

Prof. BoltDid your neighbour manufacture your scooter?

Check the exact vehicle

Look up the handbook for your model, model year and variant. Ask the manufacturer for written clarification if its current fuel guidance is unclear. Manufacturer manual libraries are a starting point. [6]

ZappyAn actual specification. How unfashionably useful.

Prof. BoltKeep the reply. It is more relevant than a confident answer about a different model.

Do not infer compatibility from a registration date, a neighbour’s experience or a generic social-media list.

EP 10

Compatibility has boundaries

ZappyIf it accepts E20, a higher blend is just extra enthusiasm?

Prof. BoltThat is not how specifications work.

Three questions, not one

Fuel-system materials, engine settings and optimisation all matter when designing vehicles for ethanol blends. Approval for one blend is not automatically approval for a higher one. [3]

ZappySo “E20 compatible” is not an unlimited subscription.

Prof. BoltCorrect. Equally, a disputed blend result alone cannot diagnose damage to a particular vehicle.

Use the manufacturer’s stated fuel requirements. Diagnose a fault separately from identifying the fuel.

EP 11

The calculator wants a headline

ZappyI multiplied a guessed mileage loss by everyone’s petrol bill. Enormous answer!

Prof. BoltAn enormous assumption has found a calculator.

Our arithmetic · invented example

At an assumed ₹100/litre, 50 km/l costs ₹2/km. At 45 km/l it costs about ₹2.22/km. That is a 10% mileage fall but about an 11.1% rise in fuel cost per kilometre.

ZappyDifferent percentages answer different questions.

Prof. BoltExactly. These invented figures explain arithmetic; they do not measure an E20 effect.

State the baseline, price and assumptions. Never turn a hypothetical example into a nationwide loss estimate.

EP 12

What would settle the argument?

ZappyA louder press conference? A taller chart?

Prof. BoltI was hoping for records someone else could examine.

The useful next evidence

Publish the sampling details and complete reports. Explain the method and whether compared tests used the same material. Resolve differences through appropriate, independently checkable testing.

ZappyAnd until then, the verdict stays open?

Prof. BoltYes. The sources reviewed here do not establish a final, independently reconciled finding for the disputed samples.

Do not average two incompatible claims. Find out why their evidence differs.

PART 4 · THE VERDICT & THE RECEIPT

A practical ending for people who need to get to work.

EP 13

OPINION · Prof. Bolt’s verdict

Bright side

ZappyCan a fuel programme have worthwhile aims and still face questions?

Prof. BoltOf course. Domestic production and energy security are legitimate goals to examine.

Hard part

ZappyAnd the ordinary motorist wants to know what went into the tank.

Prof. BoltExactly. Clear specifications, trustworthy checks and usable complaint channels are part of earning confidence.

MY TAKE

Prof. BoltDefend a policy with evidence. Investigate a suspected quality problem with evidence. Consumers deserve both.

ZappyMy agency will charge extra for certainty it cannot supply.

Prof. BoltIt will supply none.

EP 14

So what should Zappy do?

ZappyI have bought a detective hat. What else goes in the kit?

Prof. BoltThe receipt, the handbook and a notebook.

Keep a useful record

Save the receipt. Note the outlet, date, fuel grade, quantity and the problem observed.

Check before concluding

Read model-specific guidance. For persistent starting, running or mileage problems, seek authorised service advice and retain the diagnostic report.

ZappyThe symptom is a clue. Not a laboratory result.

Prof. BoltContact the oil company through its official complaint channel and keep the reference. [7]

Do not collect, mix or heat petrol for a home test. Ask for authorised investigation.

For a BPCL outlet, its official feedback page offers a Retail category. Use the relevant company for other outlets.

EP 15

Fridge-door cheat sheet

Remember

E20 describes a nominal blend. The reported 31.2% result remains disputed. Neither a headline nor a mileage change measures your tank.

Do this

Check your vehicle guidance. Keep receipts and diagnostic records. Use the fuel supplier’s official complaint process.

Deep dive

Ask for the collection record, test method and full results. Separate fuel compliance, vehicle diagnosis and the policy debate.

ZappyNew agency slogan: “Full tank. No half-tested conclusions.”

Prof. BoltFinally, something worth printing on the receipt.

ZappyShall I add the fuel’s autobiography?

Prof. BoltOnly after it produces its sources.

CASE OPEN!

Sources · the evidence drawer

All sources checked 7 November 2026. This is the evidence cutoff, not a publication schedule. The dispute may develop after this date.

[1] The New Indian Express · Karnataka’s reported findings · 6 November 2026. Secondary reporting of the State allegation and laboratory results; not an independent audit.

[2] The New Indian Express · Oil companies’ response · 6 November 2026. Secondary reporting of the companies’ joint statement and procedural objections. IS 17021 is attributed to that statement; this comic does not reproduce the standard or make a tolerance ruling.

[3] NITI Aayog / Ministry of Petroleum & Natural Gas · Roadmap for Ethanol Blending in India 2020–25 · June 2021. Primary technical/policy background, especially printed pages 16–17 on vehicle technology. Historical roadmap, not proof that every planned milestone occurred.

[4] Ministry of Petroleum & Natural Gas / PIB · Response to concerns on ethanol blending · 12 August 2025. Primary statement of government policy rationale. Policy benefits do not establish compliance of disputed samples.

[5] US Department of Energy / AFDC · Ethanol fuel basics · Undated. Primary background on fuel energy and vehicle dependence. US-specific blend permissions are not applied to India.

[6] Maruti Suzuki · Manufacturer’s owner-manual library · Undated. Example of an official manual library, not guidance for every brand or a compatibility verdict for any reader’s vehicle.

[7] Bharat Petroleum · Official feedback and complaints · Page updated 26 August 2024. Official Retail complaint entry point listed in search results. Full page access was restricted during this check; no response-time guarantee is asserted.

What remains unresolved: We have not independently inspected sealed samples, complete laboratory reports or the sampling chain. We do not establish the blend in any reader’s tank, a statewide average, vehicle damage or a final ruling. “E31” in the title is shorthand for the disputed headline result.

Calculations: Episode 11 is our arithmetic using invented assumptions, not current pump prices or observed mileage. ₹100 ÷ 50 = ₹2/km; ₹100 ÷ 45 ≈ ₹2.22/km; the increase is approximately 11.1%. Figures rounded.

Scenes & opinion: Zappy, Prof. Bolt and the detective agency are fictional. Dialogues are invented, not quotations from officials or companies. Episode 13 is opinion. Evidence-review questions and practical suggestions are editorial synthesis. Symbols are explanatory, not depictions of an actual outlet or laboratory.

Reader note: General information. Follow your vehicle manufacturer’s guidance and obtain a diagnosis for a specific fault.