Innovation engine: The new 1.8 TFSI

[AVANTI R5]

August 04, 2011 Innovation engine: The new 1.8 TFSI
Source: Audi of America
· Ample power and minimal consumption: 125 kW (170 hp) and
320 Nm (236.02 lb-ft) torque, but just 5.7 liters per 100 km (41.27 US mpg)
· New solutions in fuel injection and other fields of technology
· Fully electronic coolant regulation system

Ingolstadt - The engines in the updated A5 family set new standards for sportiness and efficiency. Even the base engine, the completely redesigned 1.8 TFSI, showcases the full extent of Audi’s technological competence. The engineers have developed innovative solutions in numerous fields of technology to achieve surprisingly strong performance with minimal fuel consumption.

The high-end four-cylinder engine displaces 1,798 cm3 and delivers a brawny and constant 320 Nm (236.02 lb-ft) to the crankshaft between 1,400 and 3,700 rpm. Peak output of 125 kW (170 hp) is achieved at 3,800 rpm. With a manual transmission, the 1.8 TFSI accelerates the Audi A5 Coupй from zero to 100 km/h (62.14 mph) in 7.9 seconds on its way to a top speed of 230 km/h (142.92 mph). Despite all this power, it consumes just 5.7 liters of fuel per 100 km (41.27 US mpg) on average, which corresponds to best-in-segment emissions of 134 grams of CO2/km (215.65 g/mile). Consumption has been reduced by 21 percent compared with the previous model engine.

Combustion behavior was a particular focus of the development work. In addition to FSI direct injection, the 1.8 TFSI also uses indirect injection. This system injects the fuel at the end of the intake manifold near the tumble valves, where it is swirled intensively with the air. Indirect injection is used in the part-load range. It reduces fuel consumption and particulate emissions to such an extent that the four-cylinder engine already complies with the limits of the future Euro 6 standard, which does not enter into force until 2015.

The rail pressure of the FSI system has been increased from 150 to 200 bar. The direct injection system is active when starting off and at higher loads. It can perform two or three individual injection operations per work cycle. To further optimize gas exchange, the valve control system has been given greater operating freedom. The Audi valvelift system, which adjusts the lift of the valves in two stages, is active on the exhaust side. The two camshafts can be adjusted through 30 or 60 degrees of crankshaft angle.

Fully electronic coolant regulation system
The innovative thermal management of the four-cylinder engine features a new fully electronic coolant regulation system. Two fast-switching, rotating cores, which are consolidated in a module and driven by an electric motor via a screw drive, control the flow of coolant. One of their primary objectives is to bring the motor oil up to operating temperature as quickly as possible following a cold start. This is done by keeping the coolant in the crankcase for a relatively long time. The cabin heating runs off of a separate loop in the cylinder head. The main radiator, which dissipates the heat to the environment, does not come into play until the latest possible moment.

The new rotating core module can set the water temperature between 85 and 107 degrees Celsius as a function of load and rpm to always achieve the best compromise between minimal internal friction and thermodynamic efficiency. Switchable valves throughout the cooling system manage heat flows between the engine, the heat exchanger for the transmission and the cabin. All together, the thermal management system reduces the CO2 emissions of the 1.8 TFSI by around 2.5 g per 100 km (4.02 g/mile).

This concept benefited from the integration of the exhaust manifold into the water-cooled cylinder head. Because this also reduces the exhaust gas temperature, it is not necessary with the 1.8 TFSI to enrich the mixture at full load, which reduces fuel consumption significantly when driving sportily.

The turbocharger in the 1.8 TFSI is also an all-new design that develops the high relative boost pressure of up to 1.3 bar very systematically. Key features include a turbine wheel made from a new alloy that can withstand exhaust temperatures of up to 980 degrees Celsius, the oxygen sensor mounted directly upstream of the turbine wheel, a pulsation damper, a compressor wheel machined from a solid blank and an electric wastegate actuator that adjusts the boost pressure particularly quickly and precisely to further reduce fuel consumption.

Engine weight has been reduced from 135 to 131.5 kilograms (297.62 to 289.91 lb). The new turbocharger/cylinder head module, a new casting process for the gray cast iron crankcase that reduces wall thickness to roughly three millimeters (0.12 in) and the crankshaft with four rather than eight counterweights and reduced main bearing diameters all contributed to this weight reduction. The pistons are made of new, high-strength alloy. Lightweight polymers are used for the oil pan, and many screws are made of aluminum.

Internal friction has also been drastically reduced by the use of an innovative coating on the piston skirts and by mounting the two balance shafts that counteract the second-order inertial forces in roller bearings. The regulated oil pump requires little energy itself, and the oil-jet cooling for the piston heads is controlled via a high-precision electric system.

http://www.audiworld.com/news/11/18tfsi/

* Registered users of the site do not see these ads.

[Predwolf]

Brilliantly engineered and designed to last approximately 12,583KMs before some obscure part fails and causes the whole thing to turn into a paperweight.

[Stanley]

Electronically controlled coolant control? VWAG can't even get their power mirrors to last more than a few years.

Innovative - yes.
Something I want to own - only if the warranty includes a loaner and free towing. Even then I'd have my doubts.

[Hites]

They sure don't play to their strong suits.

[bal00]

Originally Posted by Stanley

Electronically controlled coolant control? VWAG can't even get their power mirrors to last more than a few years.

Innovative - yes.
Something I want to own - only if the warranty includes a loaner and free towing. Even then I'd have my doubts.

And yet you bought a car from a brand that's ranked a fair bit lower than Audi.

[neg_matnik]

At least, on paper, this engine should be free of excessive carbon build-up on the intake valves. It's using regular port fuel injection in addition to direct injection (like the Toyota/Lexus D4-S system used in the Lexus IS 350 engine).

[amanichen]

Originally Posted by bal00

And yet you bought a car from a brand that's ranked a fair bit lower than Audi.

Ah yes, JD Power where a broken dome light is weighted equally with a transmission failure...

Besides, the real test is after 7-10 years and 80k-100k miles is if the vehicle is going strong and requires the expected maintenance for a car of that age, or has turned into a money pit where stuff is constantly breaking.

[bal00]

Originally Posted by amanichen

Ah yes, JD Power where a broken dome light is weighted equally with a transmission failure...

And despite that, ratings based on actual data still hold more water than the usual forum bs of people re-iterating what they read in another thread, where people were re-iterating what they read in another thread...

[Spenk]

Originally Posted by Predwolf

Brilliantly engineered and designed to last approximately 12,583KMs before some obscure part fails and causes the whole thing to turn into a paperweight.

$10 says it has a plastic water pump...just like all the other VW/Audi slag.

[jagersti]

Are you bashing subaru in comparison to audi? If so, I think you are reading your graph wrong. Subaru has 157 issues / 100 vehicles while audi has 161/100. That would make subaru more reliable, albeit by 4 vehicle issues.

[Spenk]

Originally Posted by jagersti

Are you bashing subaru in comparison to audi? If so, I think you are reading your graph wrong. Subaru has 157 issues / 100 vehicles while audi has 161/100. That would make subaru more reliable, albeit by 4 vehicle issues.

He's responding to post from a Mazda owner.

[HipToBeSquare]

Originally Posted by Spenk

$10 says it has a plastic water pump...just like all the other VW/Audi slag.

That depends on what kind of plastic. Cheap forms of thermoplastic can be crap, some not so bad. Glass-reinforced nylon and some of the more advanced plastics can be quite good.

And some pot-metals with melted scraps used for casting, can be brittle, and less than wonderful, if made cheaply, too.

[Masterauto]

Nice I hope they solved the gumming up problems in the crankcase and DI ports.

[jigga]

Originally Posted by bal00

And despite that, ratings based on actual data still hold more water than the usual forum bs of people re-iterating what they read in another thread, where people were re-iterating what they read in another thread...

It's funny how that happens, isn't it?

If these cars were as unreliable as some would have you believe, I doubt VAG would be in business today...

[shikataganai]

Originally Posted by bal00

And despite that, ratings based on actual data still hold more water than the usual forum bs of people re-iterating what they read in another thread, where people were re-iterating what they read in another thread...

You called?

[bal00]

Originally Posted by shikataganai

You called?

While the dots are cute and all, they don't contain a lot of information.

If you look at the numbers from JD Power, the difference between the worst rated brand and the best rated brand is 1.2 problems in 3 years.
The difference between an average car and a far below average car may be as little as 0.4 problems, which, in terms of time and money spent is probably less painful than one extra fill-up in 3 years. The difference between Audi and Honda is 0.22 problems in three years.

In other words, if you buy a fleet of 50 Hondas, statistically, you'll have 70 problems, and if you buy a fleet of 50 Audis, you'll have 80 problems. Reading threads like this one, you'd think that it's 0.7 vs 8000 problems.

[Godmal]

Originally Posted by Masterauto

Nice I hope they solved the gumming up problems in the crankcase and DI ports.

That's what the indirect injection is for; too many warranty claims!

[boxerinside]

co-worker's Eos convertible hardtop stopped working
I got the pleasure of telling her "I told you not to buy a VW lemon."

[hkerekes]

I have a new problem on the Beetle.

The right blinker was blinking 2x as fast. I told my wife that a light was out and it would be an easy fix.


No lights were out, I took out one working light and put it back in, the problem stopped. It blinks normally now.

[Hites]

Originally Posted by amanichen

Ah yes, JD Power where a broken dome light is weighted equally with a transmission failure...

Besides, the real test is after 7-10 years and 80k-100k miles is if the vehicle is going strong and requires the expected maintenance for a car of that age, or has turned into a money pit where stuff is constantly breaking.

On a serious note, do you think that the best metric would be "problem cost percentage of vehicle price"? For example, a $25k car needing $5k of repairs would rank lower than a $100k car needing $15k of repairs. If JDPA had something like this, would you be more inclined to take them seriously?

[Hites]

I'd really love to have an A4, but these horror stories...

[shikataganai]

Originally Posted by bal00

While the dots are cute and all, they don't contain a lot of information.

If you look at the numbers from JD Power, the difference between the worst rated brand and the best rated brand is 1.2 problems in 3 years.
The difference between an average car and a far below average car may be as little as 0.4 problems, which, in terms of time and money spent is probably less painful than one extra fill-up in 3 years. The difference between Audi and Honda is 0.22 problems in three years.

In other words, if you buy a fleet of 50 Hondas, statistically, you'll have 70 problems, and if you buy a fleet of 50 Audis, you'll have 80 problems. Reading threads like this one, you'd think that it's 0.7 vs 8000 problems.

Black dots for "engine major", "engine minor", "fuel system", and "electrical system" tell me all I need to know.

Oh, and your extrapolation from JD Power data is inaccurate: different surveys, different populations, different methodology.

[Skylab]

The power numbers from this smaller motor are impressive.
Diesel like torque and almost equal MPG's.
Economy and power figures keep getting better.

[heavyD]

Originally Posted by shikataganai

You called?

Actually that puts Audi in a pretty good light. Five year old cars tend to have more reports of engine, transmission problems and Audi engines are a lot more complex than your average Honda engine. Their transmissions look pretty bulletproof by those ratings. Besides this is a Subaru site so most here should know that a WRX or especially an STI has probably a 30% chance of being on its second engine after 5 years. Personally I'm really only interested in the first three years as that's about how long I hold on to a car and the three year reliability is stellar.

[shikataganai]

Originally Posted by heavyD

Actually that puts Audi in a pretty good light.

Uh, no, it doesn't.