VW/Audi EA888 Gen 3 (MQB/MLB) Engines ExplainedLeave a Comment
So the new VW/Audi EA888 Gen 3 motor has been out for quite some time, but I still get questions on what is new with this engine. I will try and address as many of these as possible. However, a good starting point is understanding the evolution of the 2.0T engines and where we are today. A good starting point is understanding the differences between the FSI (or EA113) engine and the TSI (EA888). Follow this link for a quick summary.
Now that we are up to speed the question is what has changed from the Gen 2 EA888 engine to where we are at today. The best way to understand that is to first understand what is driving the change. The simple answer is tougher fuel economy and emission standards globally. However, we are all a bit spoiled and don’t want to give up any power.
The engineering goals for VAG with the design of this engine were as follows:
- Reduction of engine weight
- Internal engine friction reduction
- Interchangeability of parts for all displacement and geographic region versions. Meaning fewer parts between the 1.8T and 2.0T and developed with crappy fuel availability in mind
- Increased power and torque without sacrificing fuel economy
- Improved comfort in the passenger compartment
This was all done with the following changes from the Gen 2 engine. Everything else that really matters is the same.
- Exhaust manifold integrated into the cylinder head. Cooling passages through the exhaust section area allows faster coolant heat up time for emission reduction, reduction of exhaust gas temps before the turbo allow a leaner fuel mixture at cruising and load for improved fuel economy
- Updated, and simplified, crankcase ventilation system designed to have a larger pressure difference to ambient air to reduce oil consumption.
- Updated intake manifold with stronger runner flaps to handle higher boost pressures; and hopefully fewer failures than what we have seen on the Gen 2 motors
- New style ignition pencil coils
- Dual injection (only in certain markets; meaning not the US) in the intake manifold. Meant to reduce carbon build-up and improved partial throttle fuel economy.
- New, more compact turbocharger with electric wastegate actuator, and lambda probe upstream of the turbine. Bolted directly to the head; no separate exhaust manifold
- Placement of lambda sensor (oxygen sensor for those that prefer that term) allows for faster control and correction of fuel mixture
- Use of an electric wastegate.
- Faster and more accurate response
- Higher closing force allows maximum torque sooner in the rev range
- Faster operating speed of the wastegate allows for faster boost pressure release on deceleration
- Boost pressure up to 1.2 bar, 1.0 bar more typical on prior generation engines
- New cooling system with electronic control of the coolant. Primary goal was for faster engine warm-up. Most of the emissions from an engine come from during the warm-up phase. The faster we get up to temperature the lower the emissions.
- Friction reduction
- Smaller crankshaft bearing diameters
- Reduced oil pressure; modified chain adjusters and less tension with the rest of the chain drive system the same as the Gen 2
- Piston clearance increased
- Increased use of anti-friction bearings
- Decreased valve spring pressure
- Weight Savings
- 17 lb weight reduction of block
- Lower oil pan now plastic
- .5mm reduction in cylinder wall thickness
- Use of more aluminum fasteners (remember single use on all of those when you are working on it at home)
- Balancer shafts lightened
Now you know all of what has changed. There is also an evolution of the Gen 3 motor that utilizes their B-Cycle Combustion process (now called Gen.3B). We will save all of those exciting details for another article.