These small FSI engines are fitted with a single-row timing chain , and they use a non-ratcheting timing chain tensioner. In some engines, non-ratcheting tensioners work just fine and in others, they can cause issues, especially during engine start up. In my opinion, these engines belong to the latter group. A non-ratcheting chain tensioner relies on engine oil pressure to apply tension to the timing chain.
When the engine is started after a long standstill, all the engine oil has drained to the oil sump. The only thing that applies tension to the timing chain during the first couple seconds after start up is a spring inside the chain tensioner. As the chain stretches and the tensioner becomes weaker, the engine will develop a rattling noise during start up. This noise is generated by the loose chain flopping around inside the engine.
The noise stops when the engine oil finally pressurizes the chain tensioner. In my opinion, the timing chain system in the 1. If left alone, the chain may at some point skip a couple teeth, resulting in incorrect engine timing and in the worst case a collision between the valves and the pistons.
Watch out for any timing chain noises during start up. Some may be present because of the non-ratcheting chain tensioner, but the longer they last the worse. If the car you are planning to buy sounds like the one in the video above, I recommend that you walk away from the sale or service the timing chain soon after purchasing the car. Please note that these engines, except the 1. The timing chain system in these cars is usually fine for the first couple years after the cars leave the factory.
However, as they get older, the risk of having to replace the chain or the chain tensioner increases. In my opinion, trying to reach k miles with the original chain and tensioner is very risky with the 1. The FSI system is based on a high-pressure fuel pump, a fuel rail and solenoid injectors. The high-pressure pump is driven directly off the camshaft by an extra cam lobe. This way, the rotating motion of the camshaft is converted into reciprocating motion of the fuel pump piston.
In my opinion, this is all very cleverly designed with the exception of one small part. This unlucky part is the cam follower. The cam follower is a little bucket thingy a flat tappet that sits between the pump and the cam lobe that drives the pump.
It rides the cam lobe on a film of oil — it is in constant contact. The problem with these engines lies in the fact that the cam follower can wear — even to the point of breaking a hole in the centre. The problem is exacerbated by infrequent engine oil changes and use of incorrect oil.
For this reason, buying a second-hand 2. If you unknowingly buy a car with a badly worn cam follower , you are likely to soon replace not just the cam follower but also the camshaft and the high-pressure fuel pump. Driving with a worn CF will quickly damage both the camshaft and the pump. In my opinion, VW Group should have made the cam follower a 30k miles service item. It is an inexpensive part and replacing it is easy.
The typical symptoms of a worn out cam follower in the 2. Some look fine after 70k miles and some are completely worn out after 50k miles. It all depends on the oil change intervals, oil quality, manufacturing tolerances and driver habits. Cars that failed under warranty, as well as cars, are likely to have an updated camshaft revision B , which should make the system last longer.
The bottom line is this — because all the EA engines are likely high mileage ones by now, look for cars that had the cam follower replaced or cars owned by people who are aware that the cam follower must be kept in good condition and should be inspected regularly.
If the seller agrees, you could also take the car to the dealership for a cam follower inspection. It is fairly straightforward to check for someone experienced with these engines. In the second generation of the TFSI engines EA , a roller cam follower was introduced which has completely solved the problem. Unfortunately, because of a different issue, I think that the EA is a better choice of the two despite its appetite for cam followers and camshafts for dessert.
The EA engine, released in , has a drinking problem. More will be explained below. By the way, the Audi S3 continued to use the EA engine after The second-generation 1. A larger 2. Both are an evolution of the 2. These engines use roller cam followers, which eliminate the risk of the cam followers wearing out. There have been cases of very high oil consumption in these engines. I believe this is because of small oil control rings that allow too much oil to enter the combustion chambers.
Once in the combustion chambers, the oil burns and leaves the engine as smoke. I think that VW Group engineers went too far with downsizing the oil control rings, resulting in huge oil consumption in some of these engines. I guess the design intent was to minimize friction and increase engine efficiency. According to the manufacturer, oil consumption up to 1 litre per miles approx.
This level of oil consumption would be acceptable in a car with k miles on the clock a two-stroke engine, you know, like in a moped. Some EA engines consume more than that — even 2 litres per miles km. The only permanent fix is to disassemble the engine and replace the pistons along with the rings. As you can imagine, it is very expensive. Audi even faced a class-action lawsuit in the US because of this problem. Usually, there are no obvious symptoms of high oil usage apart from smoke under heavy acceleration.
The EA engine, unlike the EA, uses a timing chain to drive the valvetrain. This engine uses a ratcheting tensioner design, which is a good thing. However, there have been cases of chain tensioner failures in these engines, resulting in a collision between the valves and the piston. The main symptom of a failing tensioner is timing chain rattle during the first seconds after engine start up.
The timing chain tensioner was updated three times. Therefore, cars made at that time may have either the updated or the older tensioner. Direct petrol injection systems, like the FSI, are prone to carbon build-up on the engine intake valves.
Excessive carbon build-up can reduce power, increase fuel consumption and make cold starts difficult. Carbon build-up is a common problem for many direct injection petrol engines as the fuel is no longer injected into the intake manifold where it has a chance to wash away any carbon build-up from the intake valves.
In any piston engine, a small portion of the gases from the combustion chamber is blown past the piston rings into the crankcase. These gases contain oil vapour hydrocarbons and combustion by-products more carbon. From the crankcase, they are fed back into the engine through the intake manifold, where they form deposits.
Also, there is the Exhaust Gas Recirculation EGR valve that redirects a portion of exhaust fumes back into the engine intake even more carbon. With direct injection, as the name implies, the fuel is fed directly into the cylinders. It is inevitable, Mr Anderson. It seems that the main contributing factor that accelerates carbon build-up is driving short distances.
If the engine rarely reaches a high enough temperature, the carbon deposits will not be burned off and they will start accumulating. The FSI and TFSI engines are happiest to do long trips and they should be revved up regularly to clean the gunk from the intake valves. If the build-up becomes severe, the only option is manual cleaning. This requires the intake manifold to be removed. To conclude, gasoline direct injection is more efficient and will save you some money at the gas station.
The design and materials haven't aged much at all either, making the A3 still feel very fresh and modern, leaving me with a car that does not feel like it has completed over 90,kms at all now! Previous View 4 images. View 4 images. View latest in Showroom. Doors and Seats 5 doors, 5 seats. Petrol 98 6. Find similar cars. All Family Cars Cars. All Audi. Owner Review. What we love. What we don't. I'd highly recommend an A3 8P to anyone in the market for such a vehicle!
Close Audi A3 Sportback 1. Our ratings explained. With Parkers you'll find the most comprehensive source of car specs online. Section 1 of 8. Change trim or engine. Power bhp bhp Acceleration mph 9. Section 2 of 8. What is the price to buy a used and new A3 Hatchback and what is the overall running cost?
Fuel consumption Pre test standard Explanation Official fuel economy tests explained. An improved official test for car fuel economy was introduced in September The new WLTP test gives figures closer to a car's "true mpg" than the pre NEDC test, which tended to overstate mpg compared to what real-world drivers would get.
When looking at mpg for two cars, always check the figures were measured under the same test system. Read the full Review of the Audi A3 Hatchback Section 3 of 8. What are the dimensions of A3 Hatchback and its fuel capacity and the overall weight?
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