Any manual for the operation of a Volkswagen Jetta says that the gasoline that must be used to refuel the vehicle is determined by the type of power unit installed. Also, the manufacturer has prudently placed a factory sticker on the inside of the fuel tank hatch, which indicates the type of recommended fuel. In the latest Volkswagen Jetta models, the choice of AI 95/98 is offered. Therefore, the obvious question arises as to what kind of gasoline is best to fill a Volkswagen Jetta car.
Car manufacturer Volkswagen Jetta recommends that its vehicles use fuels with little or no sulfur content. This is done to result in the lowest fuel consumption and to avoid serious engine damage. Volkswagen Jetta vehicles with petrol engines must be operated on unleaded fuel according to EN 228 or DIN 51626-1. Also, in extreme cases, it is possible to refuel with the presence of ethanol components up to 10% (E10).
Refueling Precautions
In cars delivered to Russia, 92 brands are adapted to gasoline. But the use of 98th gasoline instead of 95th can harm the engine and be complicated by its overhaul. It is possible to refuel a car with a higher brand of gasoline than specified in the Volkswagen Jetta manufacturer's service book, but this will not save fuel or add power to the car's engine, but it can definitely damage the engine, leading to burnt valves.
To extend the life of the engine, it is better to use gasoline with the recommended octane rating (data can be found in the service book). However, malfunctions can be a consequence of not only the wrong type of fuel. What are the main precautions to be observed after the next refueling of the car:
- If, while driving, the Volkswagen power equipment starts to work unevenly or there are interruptions in its operation (jerks), this may be caused by poor or insufficient fuel quality, for example, if water gets into it.
- If these symptoms occur, you should immediately reduce the speed and, trying not to heavily load the Volkswagen engine, at medium speeds, you must move to the nearest service center.
- If these symptoms appear immediately after refuelling, stop the engine immediately and call for technical assistance, also to avoid further damage.
If you turn to the Volkswagen Jetta manual, then it says for car owners what kind of gasoline is required, and also that AI 98 is recommended for VW engines of all modifications that were installed on the sixth generation of Jetta models, namely TSI and MPI. However, as an exception, the use of AI 95 is permissible. But, if you pay attention, there is not a single mention in the manual that AI-92 gasoline can be used in any way to refuel a car. What is the reason for this, because for generations of older years of production, this type of fuel was considered a very acceptable option. However, for cars with a worn engine, this is contraindicated, and you should not use 92nd gasoline in a car with a small engine, for example, in a Volkswagen 1.4 TFSI, the volume of which is 1.4 cc.
98th gasoline created for VW Jetta
High-octane fuel, or short AI - 98, is used for Volkswagen Jetta engines with a turbine, in particular, sports ones. It is also recommended for use for power units that have a special coating on the piston group. Its use is advisable according to the recommendations of companies producing a car engine, which must have a high degree of compression of the fuel mixture.
Tuning companies are converting engines to use this high-octane fuel. The use of 98th gasoline in ordinary Volkswagen Jetta engines that do not have such a system for high compression of the gas mixture will lead to overheating of the combustion chamber and combustion of the engine valves. The high octane mixture flares up very quickly, with open flames present. Ordinary candles are also not quite "ready" to work in conditions of high heat.
What kind of gasoline are you using?
Gasoline AI 95 gives hope for the best
At gas stations, improved 95th gasoline is offered with modified Premium or Ecto brands. Gasoline companies widely advertise that it has miraculous cleaning properties, and also adds about 15% of the power to the Volkswagen Jetta engine. As for the increase in power, it makes no sense to talk, but about the fact that it has cleaning properties, it's true. There is an opinion that additives added to gasoline to clean injectors and valves are toxic and aggressive, often leading to the destruction of the engine itself. But in reality, this is not so - the content of substances that dissolve deposits in gasoline is not so high and the constant use of gasoline with cleaning components does not harm the parts of the Volkswagen Jetta engine and can even extend its service life.
Grades of gasoline are determined by octane numbers with values from 91 to 99. The most common are 92nd, 95th, and occasionally 98th can be found at gas stations. By the way, 98th gasoline is used in cars with engines equipped with a turbine, as well as sports modifications of power plants. The best way to keep the engine of a Volkswagen Jetta in perfect condition is to refuel only the gasoline recommended by the manufacturer and at proven gas stations.
6 comments on ““VW Jetta: what kind of gasoline to fill?””
On the issue of gasoline. Jetta, release December 2013, 1.6 aspirated engine, respectively, no turbines. On the filler cap, the main gasoline is 98, 95 is allowed. Judging by the information located here, 98 is not suitable for this engine?
Explain the information presented in the table. As for the sixth generation VW Jetta for all 1.2 petrol engines; 1.6 the use of AI-92, AI-95 and AI-98 is acceptable. Since Russian-assembled cars have also been adapted to AI-92, therefore, refueling with this fuel is also acceptable, but after the warranty period has expired. But for models 1.4 (hybrid) and 2.0, strictly AI-98 is recommended. Therefore, this brand of fuel is in the bottom line opposite the last two engine modifications, but also applies to engines 1.2 and 1.6.
Perhaps there are no such car owners who have not heard about the "oil plague" - the intensive degradation of engine oil and its freezing as soon as the needle of a street thermometer drops below zero. For the first time this story began the winter before last in the Moscow region, hundreds of cars did not start at the first frost and left for service on tow trucks. For a long time, experts puzzled over the cause of this phenomenon, while journalists simultaneously tried to come up with their own versions. And if with cases when fake engine oil was poured into the engine or they simply forgot to change it on time (and in Moscow traffic jams engine oil runs out of its resource much earlier than replacement according to the regulations), everything is less clear and there are no other actors except oil, then with the TSI engines of the VAG concern, the story turned out to be somewhat different.
It was like this: For the first time in my life, I refueled a car with gasoline at a Gazpromneft gas station and after 3 days at a street temperature of -4 degrees Celsius, the engine gave a low oil pressure error ...
I have never used the services of official services (because my father has a small service) due to the fact that I am not ready to trust my beloved car. For the same reason, I am completely independent of the mythical guarantee and any bindings to certain brands. I only use years of proven solutions and have never had a problem with my cars. Considering my reverent attitude to routine maintenance and, in particular, changing the oil (adjusted for motorcycle hours and operating mode, and not just focusing on mileage), I honestly never thought that I myself would personally encounter the “oil plague”, believing that the reasons for this phenomena are really associated with fake or exhausted oil.
A few inputs. I have an Octavia Scout with one of the group's most popular engines - the 1.8TSI EA888 series. The car is 2.5 years old, mileage is 70 thousand kilometers, careful operation and all maintenance work on time. In particular, oil change every 10 thousand kilometers (assuming my average speed is 50 km/h). Mobil Super 3000 X1 5w40 oil is used with a VW 502 00 approval, the oil is purchased from an authorized Mobil dealer in 20-liter canisters. My particular instance of the engine spoils all the statistics on oil consumption - I have never added oil during the entire period of operation, and its level changes only within the measurement error (1-2 mm). The motor is operated in the entire operating speed range, up to 7000. It is mainly operated on 95 gasoline, occasionally 92 is used (spit in the face of those who gave the command to glue one single sticker 98 (95) RON / ROZ). The engine never saw gasoline with an octane rating of 98, and the first replacement of factory spark plugs was made at a run of 75 thousand kilometers!
I have a neutral attitude to the quality of gasoline, in my 12 years of experience with a mileage of more than half a million kilometers from Murmansk to Vladivostok, I have never encountered problematic fuel (although I often filled the cheapest gasoline / diesel at the most "suspicious" gas stations).
In Scout, I usually filled in the usual 95 at TNK or Lukoil, if there were no gas stations along the way and it happened far from the Moscow region - 92 was used (the CDAB engine can be operated without any restrictions on fuel with an octane rating of 91 RON / ROZ, see SSP 436, page 8). By the way, it was on 92 gasoline that I got the lowest fuel consumption for the entire time I owned a car (I drove out on a full tank of 60 liters consistently more than 750 kilometers before the light bulb), but there was no difference in dynamics.
In November 2013, on the way to a country house, for the first time in my life, I filled up a full tank of gasoline (I don’t see the point in filling up less than a full tank - I’m too lazy to constantly stop for refueling) at the Gazpromneft gas station in Naro-Fominsk, because. the tank was practically empty, and there were no more gas stations along the way. 3 days later, during the first frost when starting the engine in the morning, I heard a knock from the engine compartment and a warning to urgently turn off the engine due to low oil pressure.
What will the majority say at this point? Ha-ha, poured singed oil, so it froze!
Everything could have been so, if not for a few very important nuances. By the time of the incident, the mileage of the engine in oil from this canister was 6 thousand kilometers (that is, it has exhausted its resource by 50% without taking into account external factors). But the main thing here is something else. Let's pay attention to the statistics of similar cases described on automotive forums.
1. Oil freezes only in gasoline engines with the abbreviation TSI. In all cases, completely different oils were filled in the engines: Mobil, Motul, Castrol, Shell, etc. These were both new cars that left the showroom just a week ago, and at the age of 2-3 years.
2. Oil froze only in cars operated in the Moscow region, mainly on the south side of the Moscow Ring Road.
3. Oil froze mainly in those cars that were refueled at Gazpromneft gas stations.
Now we will not consider standard cases of engine oil freezing due to violation of operating conditions and its natural degradation (for example, the oil has worked out its entire resource in traffic jams and froze in severe frosts), as well as cases of really fake oil (for example, the case with Dexos2 factory oil on concern cars GM is a different story). This also happens, unfortunately.
ATTENTION! At the moment we only consider TSI engines!
We are now only interested in TSI engines of the VAG concern. In Skoda, for example, engineers promptly issued an order to fill in oil with a viscosity of 0w30 and a tolerance of 502 00, while leaving a service interval of 15 thousand kilometers! This is the same stupidity as sticking sticker 98 on the gas tank flap of an Octavia with a 1.6MPI engine (and they stick them on all cars, no matter what engine is under the hood). If you take 5w40 oil, which is very outdated according to modern standards, then it will freeze only at a temperature of -30 degrees! The second is the VW 502 00 approval and the replacement interval of 15 thousand kilometers - if such a car is operated in Moscow traffic jams at an average speed of 20 km / h, then it can be sent to a landfill after 5 thousand kilometers.
But let's think together, the problem only applies to TSI gasoline engines. The problem of oil freezing did not affect other gasoline engines. What can we say - the owners of diesel cars were generally out of business, although the same oils are used.
What happens - gasoline kills engine oil? But how can gasoline get into the oil on a serviceable engine. This is what we will deal with now.
TSI (Turbocharger Stratified Injection) gasoline engines are direct fuel injection and turbocharging (depending on the engine modification, it can be supplemented with a turbocharger). High pressure direct injection implies the presence of a high pressure fuel rail and a corresponding high pressure pump (high pressure pump). For many, it is still a surprise that high-pressure fuel pumps are not only on diesel engines.
Let's look closely at the scheme of the fuel system of TSI engines. Fuel from the gas tank is supplied by an electric pump through a fuel filter with a built-in pressure control valve. It is set to a pressure of 6 bar and all excess is returned to the gas tank. One line goes into the engine compartment (without a return line!), Which is connected to a mechanical high-pressure fuel pump, which is driven by a four-sided cam on the camshaft in the cylinder head. The injection pump itself pumps fuel at a pressure of up to 200 bar into the fuel rail, from where it enters the injectors. The performance of the injection pump is controlled by a controllable valve located on the injection pump housing based on data from a pressure sensor installed on the fuel rail.
The EA888 Motor Tutorial (SSP 384) explains that the motor electronics do not have low line pressure sensors and control the electric pump output based solely on motor load data. That is, in simple words: press the gas, the command goes to the electric pump in the gas tank to turn on at full power.
Why is TNVD interesting for us? This is the only place in the engine where there is a potential for gasoline to enter the crankcase from the fuel line! Of course, there are still options for gasoline to get into the oil. For example, if the engine does not start, the injectors pour fuel into the cylinders, it does not ignite and flows into the crankcase. But for this you need to try to turn the engine for a very long time without a hint of flashes in the cylinders. If we talk about a running engine, then all modern engines will instantly turn off the nozzle on the cylinder in which there is no ignition of the fuel mixture and a Check Engine error will appear.
Now back to my story. She has several interesting nuances. For two consecutive autumns, I have observed a sharp increase in the oil level in the crankcase. In the first case, I discovered this a few days after the scheduled oil change and attributed it to the fact that I did not keep track and poured more oil than necessary during the change. With the help of a syringe and a tube from a dropper, he pumped out the excess and forgot about the story. History repeated itself last year. Autumn again, but for the first time after changing the oil, I looked under the hood after about 3 weeks (there is no oil consumption - why climb there) and again found that the oil level was 5 mm above the maximum mark. Of course, the level of antifreeze was normal without changes, but the engine oil clearly smelled of gasoline. I note that there were no problems with the engine in terms of starting, dynamics and fuel consumption. Started up and drove normally. Let me remind you that I do not stand in traffic jams, my average speed is 50 km / h, and the minimum trip is usually 80 kilometers. A few days later I refueled for the first time at Gazprom Neft and after 3 more days I personally got acquainted with the frozen oil.
Then it's time to think about how autumn is different from any other season? The answer was found quickly - since the summer there has been a habit of "sit down and go" without warming up the engine. Moreover, everyone knows that the TSI engine cannot be warmed up at idle. When it's cold outside, any car owner somehow warms up the engine, at least 2-3 minutes. And in the fall, I started a cold engine in the morning, waited 10 seconds for the rpm to drop to idle and drove.
What happened at that moment in the engine? The seal on the injection pump rod on a cold engine lost its tightness and began to pass gasoline directly into the cylinder head. And since I immediately drove and pressed the gas, the engine control unit commanded the electric fuel pump to increase the pressure in the low pressure line. Part of the gasoline leaked directly into the crankcase, while the lack of sensors on this line did not allow the engine electronics to fix the malfunction in any way.
Then there was a chemical reaction at high temperature between the components of engine oil and gasoline, which led to accelerated degradation of engine oil. And here special thanks should be said to the fuel from Gazpromneft gas stations in the Moscow region. It is in its composition that there is something that leads to accelerated degradation of engine oil.
If you let the cold engine run at idle for literally 1-2 minutes (not just for heating the engine, but for the seal itself on the injection pump due to friction), there will be no increase in the oil level in the crankcase. I took measurements and came to the conclusion that if the engine was not warmed up, but immediately driven, then by the end of the trip there was an excess of oil in the crankcase. At the same time, it should be noted that if the defect were permanent, that is, the injection pump rod leaked gasoline constantly during engine operation, we would get a full crankcase of a mixture of gasoline and oil, from which gasoline simply would not have time to evaporate through the crankcase ventilation system.
It also suggests that the defect is not permanent and does not apply to all engines. It is for this reason that there are a sufficient number of cars with TSI engines that always refuel at Gazpromneft gas stations and have never encountered oil freezing. It's just that their high-pressure fuel pump does not have such a design defect, therefore, gasoline does not get into the oil.
In general, it is normal for VAG that some parts have design flaws, and even a warranty replacement of one or another part cannot always help. For example, the story of the “sweating” inlet pipe in front of the turbine is very indicative. About half of cars with 1.8TSI engines have such a problem, but many car owners do not look under the hood and do not know about it. The thing is that the turbocharger design does not imply a separate channel for relieving excess pressure (when releasing gas, engine braking) and the turbine essentially closes on itself by opening the bypass valve. All excess pressure goes back to the intake pipe (although, in fact, there can be no excess pressure in the pipe in front of the turbine from the point of view of logic), and there is a factory defect in the connection with the pipe from the crankcase ventilation and oil separator. Since some part of the oil is somehow not retained by the oil separator, it flies back into the turbine, and due to a loose weld, this oil crawls out and begins to flow down the turbine onto the drive shaft. At the same time, the official response of VW Rus says that this is “normal”. Many have changed the nozzle under warranty, but this has not helped everyone. If the joint of the two tubes is sealed with sealant, the problem disappears.
And there is a story with the high-pressure fuel pump at the Touran club, where a person was seriously puzzled by the ingress of gasoline into the oil, went to the dealer many times, where the entire fuel rail and high-pressure fuel pump were changed several times, but this did not solve the problem, and also conducted an examination:
“Fuel enters the crankcase cavity between the plunger and the injection pump housing. The replacement of the injection pump does not give the desired result and gasoline still enters the crankcase cavity, from which it follows that the design of the injection pump for the engine under study cannot ensure the sealing of the crankcase from gasoline entering it, which, in turn, is a manufacturing defect. Since the defect is detected repeatedly and reappears after its elimination, the defect is significant, the elimination of the existing deficiency is impossible.
If we take into account that most TSI engines are characterized by increased consumption of engine oil (up to 1 liter per 1000 km), then most owners may not even be aware of the fact that gasoline enters the oil through the injection pump. On the contrary, the ingress of gasoline into the oil can create a temporary illusion that oil consumption has decreased.
The conclusions here are:
First, try to buy engine oil from official representatives to reduce the risk of running into a fake.
Secondly, change engine oil not by mileage, but by motor-hours. Using the example of VW oil tolerances, the picture is as follows: Tolerance oil 502 00 has a resource of 250 engine hours, Tolerance oil 504 00 has a resource of 650 engine hours. Look at your average speed on the on-board computer and, based on this data, make a decision about changing the oil. If you drive in Moscow traffic jams at an average speed of 20 km / h, then it is obvious that your oil will work for 250 hours already for 5 thousand kilometers.
Thirdly, if you have a TSI engine, then just in case, beware of refueling at Gazpromneft gas stations in Moscow region. Especially if you noticed the smell of gasoline from the oil filler neck.
UPDATE dated January 27, 2014:
1. Did you notice a mileage inconsistency in the instructions for replacing spark plugs? The described story happened in November 2013 on a run of 70 thousand kilometers, now it is January 2014, candles were replaced on a run of 75 thousand, now the run is already 77 thousand kilometers.
2. Butthurt about 91 octane gasoline allowed without restriction on a turbocharged engine? Study the specifications for the motor, so I wrote in such detail that even a five-year-old child will understand.
3. I repeat once again - if you have a car with a gasoline engine without a high-pressure fuel pump, then this problem does not concern you, pass by. And if you have a diesel engine, then you can forget everything you read and never remember.
4. The case of oil thickening described above was the primary symptom of oil degradation - at the start, the oil pump drove the oil up, but it was not glass back into the crankcase and it began to work dry. If you ignore this warning and drive another couple of thousand kilometers, then it will be easier to throw out the engine than to pick out jelly from it.
5. For the very stubborn - 2 cars are operated on oil from one 20-liter canister: Octavia Scout 1.8TSI and BMW 320i E46 M54. In the first car, in the fall, gasoline began to intensively get into the oil, which led to its thickening at low temperatures, in the second - with more mileage, more severe frosts and operation on any fuel (including Gazpromneft), there are still no symptoms of oil freezing.
We often write about choosing the “right” gasoline, and almost always repeat ourselves involuntarily. And all because nothing fundamentally changes in the creation of an internal combustion engine: an engineer always designs it for a certain fuel. And if the instructions recommend, for example, only the 95th, then it must be filled in. Everything else is from the evil one.
There is a myth that all low-octane gasolines are obviously low-quality, but high-octane ones are just the opposite, the elite. This is complete nonsense. The same 80th gasoline is a fuel that is specially made with this octane number for engines with a low compression ratio. As for 98 gasolines, they are mainly intended for high-powered engines that require high knock resistance of the fuel. In both cases, the value of the octane number and the quality of gasoline are in no way related to each other.
In general, according to European standards, no fuel with an octane rating below 95 already exists. The EN 228 standard indicates that RON (in our opinion, this is the octane number measured by the research method) is not lower than 95. Therefore, reflections on the topic “What to fill in?” in fact, they boil down to a choice between numbers 95 and 98 - provided, of course, that the instructions for a car with a turbo engine indicate a plug of 95–98. In this case, as a rule, the same instruction recommends everyday driving on the 95th, and in extreme heat, fill in the 98th. The explanation is simple: as the temperature rises, the likelihood of detonation increases, so gasoline with a higher octane rating will be useful.
But here's what's interesting. Today, most oil companies offer us both "regular" and "improved" gasolines. There are many examples: V-Power, Ultimate, G-DRIVE, Ecto. Each liter of such gasoline costs about a ruble more than "regular" gasoline - while the consumer receives fuel with improved detergency.
At one time, we checked just the washing ability of such gasolines and can confirm: they really do it better than usual. But there is another, unpleasant phenomenon, for the sake of which the current conversation was started.
On duty, I periodically have to attend some presentations, including those dedicated to the opening of new gas stations. Around - cameras, voice recorders, speakers and a certain experimental car, on the example of which it should be clear to all the assembled guests what kind of gasoline should be poured in order to avoid trouble.
Then a strange story begins, repeating itself in different places almost like a blueprint. Reminding the audience about the dangers of detonation caused by the use of the wrong gasoline, the speaker each time offers to see for himself the merits of the “correct fuel”. And the correct one, from his point of view, is just the aforementioned "cleaners" - V-Power, Ultimate, etc. With them, there will be no detonation, and the power will jump, and the environment improve with economy. And who does not believe - here, if you please, take a look at the stand. First, we fill in a regular gasoline, then an improved one - the device immediately shows the difference.
Dictaphones swallow information, speakers radiate confidence. But by what miracle does the washing ability of gasoline raise the power of the engine before our eyes? And everything is simple: as if by agreement, representatives of completely different companies show the same trick: they compare the improved 98th gasoline with the usual 95th! Moreover, the octane number of the latter is never advertised: just "normal" - that's all. And only after a direct question they reluctantly nod - yes, the 95th.
By the way, the same nonsense is sometimes contained on the profile sites of individual companies. A typical phrase is: "The increase in mileage on one tank can be up to 39 km compared to conventional fuel." Or, for example, like this: "The unique fuel protects the engine from pollution and thus increases the power of the car." And finally, like this: "engine power can increase up to 5.7%, and vehicle acceleration can increase up to 2.6% compared to conventional fuel."
To be honest, it's not good. Because the firms do not like to admit that it is incorrect to compare gasolines with different octane numbers. And the request to provide comparative data on washing and conventional fuels with the same octane cannot be fulfilled. The explanation is simple: we have such data, but it is better to compare the 98th with the 95th, because the difference is more noticeable!
Actually, it's embarrassing. Because washing gasolines are really useful for the engine. But they give serious increases in power only if used for a long time on a dirty motor that has lost its former agility. After washing, the engine can return to its original state, thereby, as it were, increasing power - that's all. But no new motor will demonstrate anything like that. Another thing is to fill it with the 98th instead of the 95th. If the engine is designed for such a range of fuels, then a higher octane can really give a few percent increase in torque. But detergent additives have nothing to do with it.
So fill V-Power and Ultimate or not? My personal opinion - yes! I always fill my car with only such fuel. But not in order to gain extra horses, but to maintain cleanliness along the entire route of gasoline. After all, detergent additives, to be precise, should not only wash, but also prevent the formation of dirt. And I don't like dirt.
