BMW N20 4 Cylinder Modern Engine

All light weight, high output four cylinder engines  has some weaknesses which is inevitably showing a learning curve from their respective manufacturers.

The issue at hand is multiple fold, in one hand high output is a trend and a side effect of removing friction and removing mass from inside an internal combustion engine. Even tough many of the most well known manufacturers are building engines over a hundred years plus, worth to say no one is exempt from the occasional flop while they are working hard to try to squeeze the most out of this ever shrinking engines.

N20 4 cylinder BMW engineN20 4 cylinder BMW engine

Here is one example, the BMW N20 4 cylinder engine which has a timing chain issue at hand. Naturally the engine is in typical BMW fashion very innovative except it  is prone to timing chain issues which is related to variable oil pressure.

The problem cause by  the ECO mode on the automatic transmission, which consequently lowers the engine rpm allowing higher crankshaft oscillations at low engine rpm.

We have performed myriad of chain replacements, naturally with the newer genuine revised components. Timing chain replacement on a  BMW N20 4 cylinder engine is a major repair due to the complexity of the proper procedure which must be followed.

How may we help, any questions?  Telephone: (1) 905.795.0419


Read more about BMW N20 engine’s timing chain and oil pump chain issues.

BMW N20 timing chain and oil pump chain issues

Why does early timing  chain stretching happen?

There are multiple factors contributing to this problem, not withstanding the 8 speed automatic transmission is one of the factors in my opinion. North American drivers prefer their cars to be automatic, in this case, the automatic is more economical, than the standard version which is preferred by the Europeans.

You may ask; Why is there a problem with the 8 speed automatic? The problem occurs with our driving habits and the programming of the automatic transmission. In normal ECO mode (the default mode) it will shift up quickly and efficiently to the highest possible gear to keep the fuel consumption at minimum, hence called the ECO mode.

N20 4 cylinder BMW engine 4 Cylinder BMW  N20 Engine

The quick up-shifting in daily driving will keep the engine’s rpm very low, which will cause the 4 cylinder engine to oscillate a lot more than would have been, if it driven on the autobahn at high rpm, where there are no oscillations are really present.

Naturally the chains, the guides are fairly weak design to make them light as possible. Our stop and go driving at low engine loads paired with an efficient automatic exacerbates the problem. Furthermore the extended oil changes also does not help to keep the whole thing properly lubricated for long life.

Needless to say the newer engines and their timing chains has been extensively redesigned to counter this common and often fatal problem.

In any case, if the chain makes noise it must be addressed immediately. All the components has to be replaced. For replacement, only an improved version available from the manufacturer. The replacement components must include the oil pump drive assembly as well, according to BMW repair instructions, also a revised, improved component.

There are multiple special tools required and attention to detail is essential to complete this rather delicate repair procedure properly and permanently.

 BMW timing chain guard
You can see on the above photo a broken timing chain guard and a clogged oil pump pick up, which could be fatal to the engine.

In case you have any additional questions please don’t hesitate to ask. We are here to help. Thank you for your time and all the best.

Telephone: (1) 905.795.0419


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