If the tank was outright counterfeiting, the motor will either not start, or not start the first time. In any case, you start driving after filling listen closely to the power unit. From the first hundred meters passed he can start tapping at the moment of pressing on the gas pedal. It shows the detonation of a failure of the engine, when fuel combustion takes place earlier than necessary.

it is also Possible jerks in the movement and instability of revolutions of the crankshaft. Such a behavior of the machine is a good reason to stay and return to the ride at a suspicious gas station. Here, upon presentation of a receipt at the gas station, they should demand an explanation from staff and to request examination.

In case of failure caused by independent experts, and along with the traffic police. Suspicious fuel from the fuel tank should be drained later, which makes sense to use tow truck and tow the car in service.

However, in some cases, after refueling at the gas station suspicious strong detonation motor is not observed, but nevertheless in the eyes of the reduced throttle response of the car, blunted reactions to the gas supply and the engine, as they say, stops to pull. Consider yourself lucky if the cause of “vegetable” reactions was to refuel with petrol with a low octane number.

In this case (if the tank is not full) you can just pour the good fuel on proven or credible network of the gas station. In other cases it makes sense to completely drain the fuel from the tank, and it is also possible to flush the fuel system.

the Litmus test in the literal sense could become a regular sheet of paper. Store it with the fuel that caused your suspicion. If the substance is greasy and quickly dries, it is an indication that the fuel is replete with impurities.

Black smoke from the exhaust pipe after filling may indicate that you have filled an absolute counterfeit, or, alternatively, diesel fuel instead of gasoline or Vice versa (the effect of black smoke can cause additives that do not match the type of your engine).

However, most often we are talking about counterfeit fuel that cannot burn and is displayed together with the exhaust gases. The particular diesel units.

Here is a black exhaust – not always the indicator of emergency. The reason may be, for example, pollution of the air filter.

Filling of poor quality or low octane gasoline usually also leads to sharp increases fuel consumption, what sooner or later will signal the cluster.

the Overrun can occur because of clogging of the fuel filter (the control unit will attempt to normalize the supply of fuel and to send a signal about the need for long openment of the nozzles), failure of the sensor mass air flow (it is either clogged, or the signal disappears in the power connector), and when coked exhaust ports cylinder head or clogged catalytic Converter.

One of the most common reasons that “tidy” has lit up the Check Engine inscription (as an option – yellow or orange icon of an engine) – poor quality air-fuel mixture or high in oxygen-containing additives (oxygenates), designed to increase the octane number. Another option is dirty injectors, a problem with the spark plugs, the fuel pump, catalytic Converter and even insufficiently clad cap of the fuel tank.

Again, that after identifying any of the above signs makes sense to merge without the rest of the fuel from the tank, and in some cases to flush the entire fuel system, replace filters, clean injectors, remove, inspect and maybe replace the plugs.

it is possible that you have to change the fuel pump, and possibly also some sensors (particularly the lambda probe), catalytic Converter. Hence the obvious conclusion – refuel only on proven gas stations network and listen to the behavior of the machine, to identify deviations in the fuel system.