MT Auto Parts Blog | Expert Tips for BMW enthusiasts on BMW Parts, Accessories, Engines and More

Image: BMW I3 Series Complete LCI LED Headlight, left passenger side, for sale at MT Auto Parts A light mist that appears overnight, then clears once the headlights have been on for a few minutes is one thing. A persistent, heavy condensation that sits inside the lens and does not shift is quite another. Both look similar from outside the car but have different causes. And only one of them actually requires a BMW headlight replacement . Here is how to tell which you are dealing with and what to do about it. Normal Condensation vs a Genuine Fault BMW headlights are not completely sealed units. They contain a small breather vent, sometimes described as a pressure equalisation tube, that allows air to move in and out as the unit heats up and cools down. This vent is intentional and necessary. Without it, repeated pressure changes would eventually compromise the housing. The trade-off is that the vent allows moist air in, which can produce a light condensation film on the inside of the len...

Image: BMW B47C20B Complete Engine with just 50K miles for sale at MT Auto Parts for £3,199.99 It's one of the most common questions when sourcing a used BMW engine : does the donor vehicle's model have to match yours exactly, or can you use an engine from a different car in the same family? The answer is more nuanced than a simple yes or no, and getting it right makes the difference between a straightforward replacement and a job that turns into a very expensive complication. The Engine Code Is What Matters, Not the Model Badge BMW has used the same engine across multiple models throughout its history, and this is where the opportunity lies when buying a second-hand BMW engine. The B47 2.0-litre diesel, for example, is found in the F30 3 Series, the F25 X3, the F15 X5 20d, the G30 5 Series, and a number of other platforms. If you are replacing a failed B47 in an F30, you can source a B47 from a written-off X3 or 5 Series and use the same engine, because the engine itself is t...

Photo by Krish Parmar on Unsplash There are few design elements in the car industry with a history as long or as contested as the BMW kidney grille . It has been narrow and elegant, wide and corporate, shrunk to almost nothing on a racing car, and ballooned to the point where it dominated an entire front end. It has sparked some of the most heated arguments in automotive design circles, generated more online commentary than almost anything BMW has done in decades, and yet, through all of it, remained instantly recognisable as BMW. Here is how it started, and how it got here. 1933: The BMW 303 and the First Double Kidney The BMW front grille as we recognise it today was born in 1933, on the 303, the brand's first six-cylinder model, launched at the Berlin Motor Show. Designer Fritz Fiedler divided the radiator grille into two vertical shapes with a chrome centre bar, rounded at the top and bottom. The BMW emblem sat between the upper arches. It was a practical design in part, the sp...

Photo by Benjamin Brunner on Unsplash Run-flat tyres divide BMW owners more reliably than almost any other topic. Some swear by the peace of mind they offer; others have switched them out at the first opportunity and never looked back. Both positions have genuine merit, which is why understanding exactly how they work and what the honest trade-offs are matters before you are standing in a tyre centre deciding on pressure. What Are Run-Flat Tyres? A run-flat tyre uses a reinforced, self-supporting sidewall, considerably stiffer than a standard tyre's, that can carry the vehicle's weight even when the tyre has completely lost air pressure. BMW's run-flat specification, known as a Self-Supporting Runflat (SSR), allows continued driving at up to 50 mph for up to 50 miles after a puncture, giving the driver time to reach a garage rather than being stranded at the roadside. This operating limit, 50 mph for 50 miles, is the key figure to remember after a pressure loss. Exceeding e...

Photo by Yoab Anderson on Unsplash The BMW Start-Stop system ​ is one of those features that most BMW owners barely notice when it is working. The engine cutting out smoothly at the lights and restarting the moment you lift the brake is almost imperceptible in normal driving. But when it stops working correctly, or when it seems to stop working for no obvious reason, it can be genuinely confusing. The system depends on a surprisingly large number of conditions all being met simultaneously, and a single sensor reading outside its expected range is enough to disable it entirely. This guide explains how the BMW start-stop system actually works, why it disables itself, sometimes legitimately, sometimes because something has genuinely failed, and what the most common faults are and what they usually point to. How the BMW Start-Stop System Works BMW introduced start-stop technology as part of its EfficientDynamics programme, with the system first appearing in a production BMW in 2007. The i...