Our Standards

Corrections & Data Accuracy

We publish corrections openly, with dates and explanations. If we get something wrong, we correct it and log it — this page is our public record of every substantive change we have made.

Corrections and editorial accuracy at BMW Engines UK — a transparent corrections log
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12
Corrections
Logged
0
Unresolved
Issues
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2025
First
Correction
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Part of
Engine Finders
Network

We are an independent editorial resource, not a garage. We publish corrections openly, with dates and explanations. If we get something wrong, we correct it and log it — this page is our public record of every substantive change we have made.

Full correction log, our correction policy, and how to report an error, below.

Our Approach to Corrections

We are accountable to the data, not to the suppliers. If we publish an error, we correct it openly and log it permanently.

Every number on this site carries a data tag ([EM-VERIFIED], [EM-QUOTE], [PATTERN DATA], or [THIRD-PARTY]), but tags do not make us immune to error. We rely on multiple sources — enquiry data, specialist interviews, third-party market data — and sometimes those sources are updated, corrected, or found to be inconsistent.

When that happens, we update the affected page, note the correction in this log, and, where relevant, add a correction notice directly on the page itself. Our editorial standards and data verification pages set out the broader framework.

The Types of Corrections We Make

Not all corrections are the same. We distinguish between three categories.

📊 Data Corrections

Changes to quoted figures — costs, volumes, percentages, mileage ranges — where the underlying data source has been updated or a transposition error has been identified.

🔧 Technical Clarifications

Refinements to technical descriptions — failure mechanisms, engine codes, fitment details — where specialist feedback or new evidence shows the original wording was incomplete or misleading.

📝 Editorial Updates

Changes to language, clarity, or framing that do not affect factual substance but improve accuracy or reduce ambiguity — e.g., replacing "all N47 engines" with "N47D20C and N47D20A variants".

Our editorial standards set out the bar for each type.

Our Correction Process

How we identify, verify, and publish corrections — step by step.

  1. Identification — Error identified via internal review, reader report, specialist feedback, or data-source update.
  2. Verification — We cross-check against the primary source (proprietary data file, specialist interview notes, manufacturer TSB, etc.).
  3. Correction — The affected page is updated. If the change is substantive, a correction notice is added to the page.
  4. Logging — The correction is entered into this log with date, page, original text, corrected text, and rationale.
  5. Notification — For significant corrections, we alert subscribers and update the editorial changelog.

Full details on how we handle corrections are on our editorial standards page.

Corrections Log

Every substantive correction we have made, from newest to oldest.

DatePageOriginalCorrectedRationale
2026-02-15 N47 Timing Chain Failure Reconditioned supply cost: £2,800–£5,000 Reconditioned supply cost: £3,200–£5,500 Updated supplier quote data from Q1 2026 [EM-QUOTE] showed higher average prices; reconditioned units now reflect current market.
2026-02-01 N47 Knowledge Centre Fitment: "3 Series E90, F30, 1 Series E87, F20, X1 E84" Fitment: "3 Series E90, F30, 1 Series E87, F20, X1 E84, 5 Series F10, X3 F25" Our proprietary enquiry data [EM-VERIFIED] showed significant request volume from F10 and F25 owners; we had omitted them in the initial fitment list.
2026-01-20 N47 Cold Start Rattle — Symptom Hub "Timing chain tensioner failure is the only cause of cold-start rattle on the N47." "Timing chain tensioner failure is the most common cause of cold-start rattle on the N47, but turbocharger wear and VANOS solenoid issues can also produce similar symptoms." Specialist interviews [EM-INTERVIEW] highlighted that turbo wear and VANOS faults can mimic chain rattle. We updated the page to reflect the broader diagnostic picture.
2026-01-05 Is an N47 Failure a Write-Off? Scrap threshold applied: 70% of vehicle value. Scrap threshold applied: 70% of vehicle value, with note: "For E90 and E87 hosts under £4,000, the 70% threshold is reached at £2,800 — evaluate scrap first." Reader feedback highlighted that the generic threshold lacked specificity for lower-value chassis. We added chassis-specific guidance.
2025-12-10 N47 Failure Rate — Data Page Failure rate: "Approximately 12% of N47 engines develop timing chain issues by 100k miles." Failure rate: "Our data shows 12% of N47D20C engines develop timing chain issues by 100k miles [EM-VERIFIED], but the rate varies significantly by chassis — E90 and E87 show higher proportions than F30 and F25." Proprietary data refinement [EM-VERIFIED] allowed chassis-level breakdown; we corrected the generalised statement to reflect the variance.
2025-11-15 N47 Oil Capacity — Technical Reference Oil capacity: 5.0 litres (with filter) Oil capacity: 5.2 litres (with filter) for N47D20C; 5.0 litres for N47D20A BMW TSB [THIRD-PARTY] confirmed variant-specific oil capacities; we had incorrectly listed a single figure.

Full archive of all corrections, including minor editorial updates, is available on request. Our data verification page explains how we audit and correct data.

Report an Error

If you spot an error on this site, we want to know.

We take accuracy seriously. If you find a factual error, a broken link, or something that seems outdated, please let us know. We will investigate, correct if necessary, and log the change.

To report an error, please use our contact page and include:

We aim to acknowledge all error reports within 48 hours and, where substantiated, issue a correction within 5 working days. Our editorial standards and specialist vetting pages set out our commitment to accuracy.

Frequently Asked Questions

Do you correct errors without telling anyone?

No. All substantive corrections are logged on this page, with dates, original text, corrected text, and rationale. Minor typographical or grammatical fixes are not logged but are still corrected.

How do you decide what counts as a "substantive" correction?

Any correction that affects a quoted figure, a technical specification, a failure pattern, or a recommendation is logged. Changes to wording that do not affect factual substance are not logged but are still made.

Can I request a correction if I disagree with your interpretation?

Yes. We welcome feedback. If you believe our interpretation is incorrect, please use the contact page with supporting evidence. If we agree, we will correct and log it. If we disagree, we will explain why.

Do you correct third-party data?

We use third-party data (e.g., Auto Trader valuations, manufacturer TSBs) with explicit sourcing. Where that data is updated or corrected by the source, we update our pages accordingly and log the change.

What about corrections to case studies or data reports?

Corrections to case studies or data reports are treated with the same rigour. They are logged here, and any affected chart or table is updated and annotated.

Every Correction Logged We maintain a permanent, dated record of every substantive change we make.

Data, Not Opinion Corrections are driven by data updates, specialist feedback, or verified reader reports — never by supplier pressure.

Transparent Process Our correction process is published in full, including how we verify and log changes.

Not a Garage We research and route. We never claim to do the work — and we correct openly when we get it wrong.

Have You Spotted an Error?

If you have found an inaccuracy, please report it via our contact page. We are committed to getting it right.

REPORT AN ERROR → READ OUR STANDARDS →