Third newcomer in the ISTA Expert mode since May 2022: Valvetronic. Undoubtedly – Valvetronic is one of the most complicated hubs in the BMW engines of our time. The mechanical part of high precision (inlet valves should be managed with several micrometers). The electronics can not be left behind (the […]
Today I visited my friends at Bavarian Workshop – a small service center, which specializes in the repair of BMW vehicles. Current patient: E66; 745Li with N62B44 engine. The engine had abnormal idle, which normalized, only when Valvetronic was disconnected. For the engine, preventive maintenance was done, gaskets were […]
Every repair of Valvetronic is time-consuming and expensive, so the question – what symptoms are characteristic exactly to the defects of Valvetronic – is very important. As already mentioned in previous entries regarding Valvetronic, it’s impact and main problems could be characteristic exactly to idle and/or in range of […]
In several forums and blogs, I’ve seen a “copy/paste style” recital about the problem, which is characteristic to Valvetronic of Generation 1. Here, the image: With A in the image the place of the hub, where, according to the author of the version: when it wears, the move of the […]
And finally – one more argument, which doesn’t talk in favor of HVA. In the first two images: the opening of the valve (shape). In black color (A): a perfect valve opening in idle (0.4 mm), in red color (B) and (C) – two problematic cases, when in a result […]
To make it easier to recognize the defects, I made a diagram – Valvetronic, Generation 2. Legend: inner circle – (deterioration): speed of wear middle circle – the impact of wear (absolute) outer circle – the impact of wear (change of shape and individual impact to cylinders) +ext – the […]
In this entry we will look at possible defects of Valvetronic components due to wear, and what effects these defects have on the valve lift. We assume, that BMW AG has manufactured perfect details, and they are damaged exactly due to wear. First basic thing – components, which rely […]
Sometimes we hear allegation – what can be changed in an internal combustion engine for several tenths of years? Everything is the same! Actually, there are a lot of changes. In this entry – about several hubs, which has changed to unfamiliarity. Why the whole entry is dedicated to this […]
Valvetronic is, most probably, the most hated hub of the BMW engine. In the same time, it’s “last hope” of the engine repair specialists – if they are not able to find the cause of the problem, most probably, Valvetronic will be the one to blame. Of course, sometimes it […]
At the first moment, it seems that everything is simple – the fuel mixture either is or is not ignited. In the second case, there is a misfire. Yes, actually it is. At the first moment, it seems – if there is a spark, everything is fine; if there is […]
