Audi developed the EA111 series of internal combustion engines under the supervision of Ludwig Kraus and presented them in 1974 in the Audi 50 and, shortly after, in the first Volkswagen Polo.
The EA11 production is a collection of water-cooled inline three-and inline four-cylinder petrol and diesel engines with various displacements to which the VW/Audi 1.2 TSI/TFSI engine belongs. This family features a lot of technologies that can be seen in other engines but are more innovative and futuristic on the period it was released.
What are VW/Audi 1.2 TSI/TFSI EA111 Engines?
The 1.2 R4 TSI/TFSI (EA111 family) is an engine that firstly replaced the same displacement naturally aspirated version of this series but with three cylinders – so it’s basically like having two different engines in one. The new turbocharged design makes for better efficiency and power, plus greater fuel economy as well.
You’ll be able to go farther on just a single tank than before because these cars will use less gas, especially now that there is no such thing as “idle stop” mode anymore, either when going up hills or slowing down at traffic lights.
This engine is part of the long0running EA111 production with the cylinder head of this overhead camshaft engine is crossflow along with camshafts driven by a toothed belt from the crankshaft; this belt also drives an intermediate shaft, which controls the oil pump, ignition distributor, and coolant pump internally.
The alternator and power steering, as well as the air-conditioning pump, are also “V” belt-driven accessories. The exhaust side is towards the car firewall in transverse mount configuration; in longitudinal mount configuration, the exhaust side is to the right as you face forward in either left or right-hand drive automobiles.
Engine Specifications and Design:
- Production Run: 2005 – 2017
- Cylinder Head Material: Aluminum
- Cylinder Block Material: Aluminum
- Configuration: Inline 4
- Bore: 71.0 mm
- Stroke: 75.6 mm
- Valvetrain: DOHC four valves per cylinder
- Displacement: 1.2 L (1197 cc)
- Compression Ratio: 10.5
- Weight: 214 lbs.
- Maximum HP: 105 HP at 4,500 – 5,000 RPM
- Maximum Torque: 129 lb-ft at 3,500 – 4,100 RPM
Engine Design:
1. Cylinder Block
Instead of the 1.4-liter version’s grey cast iron engine block, the 1.2 TSI/TSFI features an aluminum cylinder block with cast iron sleeves liners. The bore size was lowered from 76.5 mm to 71.0 mm. However, the stroke remained the same at 75.6 mm.
The new die-forged steel crankshaft and cast aluminum alloy pistons were also installed at the bottom end. All of the moving parts were lighter in this engine release.
2. Cylinder Head
An aluminum alloy cylinder head sits atop the engine block. It features two valves per cylinder -for a total of eight valves, and a single overhead camshaft layout. It is a tremendous challenge for tiny displacement engines to make them more enjoyable to drive due to a lack of torque. However, the two-valve heads produce higher torque at low and mid-range rpm, as showcased in this example.
The diameter of the intake valve is 35.5 mm, while the diameter of the exhaust valve is 30.0 mm. The engine has a non-serviceable timing chain along with the roller finger cam followers with hydraulic tappets to operate the valves requiring no valve clearance adjustment.
3. Turbocharging
The VW/Audi 1.2 TSI engine is outfitted with an IHI 1634 turbocharger. The maximum boost potential reaches 1.6 bars or 23.2 psi. The water-cooled intercooler built into the intake manifold cools the compressed air, and the engineers also added an electronically controlled “E-Gas” throttle valve from Bosch.
The Fuel Stratified Injection (FSI) system is installed in the engine; thus, its name string. The camshaft-driven high-pressure injection pump delivers 2,180 psi of fuel pressure. The fuel is injected directly into combustion chambers by consecutive fuel injectors.
As for the common EA111 engines, the ignition system is entirely electronic, with each spark plug controlled by its own spark coil. The Siemens Simos 10 electronic engine control unit (ECU) is used in the 1.2 TSI/TSFI engine.
Applications of VW/Audi 1.2 TSI Engine:
- Volkswagen Polo Mk5
- Volkswagen Beetle A5
- Volkswagen Gold Mk6
- SEAT Ibiza
- Volkswagen Caddy
- SEAT Leon 1P
- SEAT Altea XL
- SEAT Toledo KG
- SEAT Altea
- Skoda Octavia
- Skoda Fabia
- Skoda Yeti
- Sokda Rapid
- Audi A1
Engine Modifications, Upgrades, and Tuning
We know that there’s a lot of things out there about tuning parts and what makes one better than another. We’ll get you the best power gain for your money; it will be easy because these parts and recommendations are easy to do.
The first is changing your EA111 camshaft. It will significantly increase engine torque. So, choosing a higher performance camshaft profile increases torque and overall efficiency.
There are different types, varying from application and build. Fast road cams often improve performance over the rev range; you may compromise a little bottom-end torque, but the high-end rpm power will be increased.
Motorsport cams boost the high-end rpm power range, but the car does not idle smoothly, and low-end power almost always suffers as a result. Driving in heavy traffic with a Motorsport and racing camshaft is not ideal. You should preferably match your power band to the usage of your vehicle, therefore for a daily driver, go with a moderate fast road EA111 camshaft.
The torque improvements you’ll get are also affected by the engine timing, injectors, and fuel pump. Changing the valve durations can change the torque band, and on most engines, the exhaust and intake durations do not have to match; nonetheless, while most cams and tuners employ matched pairs, there are certain benefits to increasing the intake or exhaust durations.
Problems Surrounding VW/Audi 1.2 TSI/TFSI Engine:
The EA111 engines are generally reliable and solid units, as long as you follow the manufacturers’ service schedules. Few problems should happen, especially if they’re regularly serviced or maintained with high-quality oil to ensure longevity. But, no engine is perfect, and some issues might occur down the road.
Some of the issues that the engine might encounter are:
1. Stretched Timing Chain
The most typical problem in the VW/Audi 1.2 TSI engine is a stretched timing chain and a failed timing chain tensioner. That is possible with relatively low mileage – between 40,000 and 60,000 miles.
At this time, the life of a 1.2 TSI engine should be separated into two parts: before (EA111) and after (EA211). The initial structures encountered serious chain-drive issues. The camshaft with eight valves is a distinguishing characteristic. Following an upgrade in 2012, the engine now has 16 valves and a belt drive rather than a chain.
In addition to that, the engine vibrates a lot. However, this is normal cold engine action. Also, if you reside in a cold environment, you should be aware that the engine only heats up when it is under load.
2. Other issues
The initial engines, in particular, are prone to issues with the cylinder head gasket, exhaust cleaning system, control electronics, and higher oil consumption. There were certain situations where the engine and its components were replaced under warranty.
It’s worth discussing the turbocharger, too, since there are intermittent issues surrounding the component. The mechanism in charge of controlling its functioning did not always perform properly.
3. Maintenance and Longevity
High-quality gasoline -at least 95 RON ultra-low sulfur unleaded petrol (ULSP) and engine oil are necessary for this engine to last longer. The engine’s dependability is also affected by the owner’s driving behavior and the frequency with which it is serviced. The 1.2 TSI engine has an average lifetime of 150,000 miles.
Summary
The Audi/VW 1.2 R4 TSI/TFSI engine is 55 lbs. less than the 1.4l TSI engine and produces adequate power and torque for a compact city vehicle. The major goal, replacing aging 1.6L engines, was met by combining a contemporary fuel injection system with a turbocharged intake.
The new 1.2 TSI debuted in 2005 and was introduced to the market, while its predecessor was still in production until 2017.
The 1.2 TSI engine was a completely new design when it came onto the market in 2005 and has undergone many improvements since then, with most changes happening under VAG’s hoods where they are usually trying out different technology for upcoming models or simply adding more power on top of what already exists there instead.
Whether this should be your next car depends entirely upon how much you enjoy driving stick-shifts during urban environments like inner cities rather than country roads only because while both types do exist within these cars, one will offer better gas economy whereas another might have pinpoint handling at high speeds depending which version is chosen.