Rigid brake pipes excessively corroded on the BMW Z4
Rigid brake pipes excessively corroded on the BMW Z4 is recorded on 12,263 tests — 10.1% of all its MOT tests, against 4.6% across every car in the data. That is 2.2× the national share.
Is this unusual for this model?
| Compared with | What it says |
|---|---|
| Every car in the data | 4.6% of tests record it — this model is 2.2× that share |
| The 318 models compared | 74 of 318, highest first |
| The model's own record | 121,314 tests · every year of the Z4 → |
A share of tests is not a probability for your car: it counts every BMW Z4 tested, whatever its mileage, service history and use. The like-for-like comparison on the model page is the fairer number.
Year by year
In 2003, 8.8% of this model's tests recorded it; in 2016, 0.3%. The share has fallen 8.5 points over that time. Worst year 2006 at 13.1%; best 2014 at 0.3%.
| Year | Failures recorded | Tests | Share of tests |
|---|---|---|---|
| 2003 | 2,445 | 27,654 | 8.8% |
| 2004 | 2,775 | 22,360 | 12.4% |
| 2005 | 2,015 | 15,376 | 13.1% |
| 2006 | 2,872 | 21,882 | 13.1% |
| 2007 | 1,801 | 22,428 | 8.0% |
| 2008 | 48 | 13,198 | 0.4% |
| 2009 | 43 | 8,488 | 0.5% |
| 2010 | 72 | 13,636 | 0.5% |
| 2012 | 45 | 12,874 | 0.3% |
| 2013 | 39 | 5,414 | 0.7% |
| 2014 | 39 | 12,976 | 0.3% |
| 2015 | 32 | 5,327 | 0.6% |
| 2016 | 14 | 4,110 | 0.3% |
Years with fewer than 0.2% of tests recording the item are left out: a year with two failures in 400 tests is noise, and this table is not here to make noise look like a trend.
What it costs
A typical UK repair for this item is £80–£180 fitted. It is a job for a garage, not a driveway. What the part is, and what to buy →
Prices are typical UK supply-and-fitting estimates, not quotes. What happens if it fails covers the retest rules.
Where this sits
- Rigid brake pipes excessively corroded: every model, every year → — the item's own page, with the part guide.
- BMW Z4 MOT pass rate by year → — the model's whole record, and what else it fails on.
- Every BMW model →