Error codes P0030, P0031, P0032, P0036, P0037, P0038. VAZ and methods for their elimination.

Error 0303 Priora 16 valves causes

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Lada Priora 2170 2007
126 engine, pistons from 124. Bosch ECU 7.9.7. On the on-board vehicle, errors 0300 and 0303 appeared. We swapped the coils for 2-3 pots, and an error about the third pot appeared again. the candles waved in places, again in the third. Why dig guys? Thank you. and greetings from the Samara branch

p.s. Mordovia is covered in snow, let's ask, how's the weather?

Dig into the compression

Pagoda Shvakh, slush snow melted in the southern Urals

check the wiring to the coil

A year ago I encountered something similar. As a result, a leak in the injectors was first detected (along the way I changed the gaskets in the manifold, etc.) and after a while it became clear that the mass air flow sensor was tired.

Therefore, on a cold engine, take carb cleaner and spray it near the ramp and manifold. By the reaction of the engine you will understand what and how.

Check the MAF voltage when the ignition is on, but the engine is not running. The new one will show 0.996. According to various sources, the upper limit is 1.05. But in practice, with this indicator, the motor will still work.

The compression on my 1st cylinder was 1 unit different from the others - that’s where the leaks occurred during suction.

Next, decarbonization, replacement of gaskets and rubber bands, crimping with new clamps and everything became a herringbone.

As for the injectors, I don’t quite understand how they can be modified with a filter and mesh. When I removed my rings to replace them, I put them on the stand purely for fun - they worked well.

Source

Error P0303

Technical description

Cylinder 3 - misfire (ignition)

Cylinder 3 – misfire detected

Symptoms

• check engine light is on or blinking
• uneven engine operation (troit)
• difficult engine starting

Causes

• faulty spark plug
• faulty high voltage wire
• faulty ignition coil
• faulty fuel injector
• faulty oxygen sensor/sensors
• exhaust valve burnt out
• faulty catalytic converter/converters
• lack of fuel
• bad compression
• Engine control module (PCM) is faulty

Repair recommendations

First of all, it is recommended to look at the manual (specialized literature) on the maintenance and repair of your car.

The P0303 code means that the vehicle's computer has detected that one of the engine's cylinders is not working properly. In this case it is cylinder number 3 .

If there are no symptoms, the easiest thing to do is reset the code and see if it comes back.

If the engine runs rough (troubles), check all wires and connectors that lead to cylinder No. 3 (including the spark plugs).

Depending on how long the ignition components have been in the vehicle, it may be a good idea to replace them as part of your regular maintenance schedule.

It is recommended to check the spark plugs and spark plug wires. Next, check the ignition coils.

It is also recommended to measure the compression.

In some cases, the catalytic converter fails.

In other cases, the fuel injectors may be faulty.

Source

Decoding codes

Well, if you succeed in checking your car for faults, then you need to decipher the combinations of errors, otherwise why do you need diagnostics at all?

Self-diagnosis

Let's look at the decoding of combinations of faults that you can read when checking the Lada Priora yourself.

The arrows on the dashboard move to maximum values ​​when performing self-diagnosis of the vehicle, and all icons on the panel are lit

Please note: if the button for switching functions of the on-board computer is not pressed for more than 10 seconds, the instrument panel will return to operating status.

Failures in the ignition system

If you were unable to check your VAZ Priora yourself, you can do this using a special tester. In this case, the error code will be a combination of a letter and four numbers:

• P - means a breakdown in the operation of the electronic systems of the internal combustion engine;
• C - malfunction of the chassis;
• B - breakdown in the electronics of the car interior;
• U - indicates an error in the joint operation of different systems;
• the number 0 indicates the OBD-2 code;
• 1 and 2 - enterprise code;
• 3 - reserve code.

Connector for self-diagnosis of a VAZ Priora car

Fuel and air system error codes

How to read errors?

In order to read errors, you need to connect a laptop or tablet PC to the car via a special K-line cable. Let's look at what tools will be needed to connect the car to the computer and determine error codes:

1. K-line cable.

   K-line cable for connecting a laptop to a car

2. Laptop or tablet.
3. Special software.

In order to connect, you need to find a connector for the cable. It is located under the steering column. Now you need to connect the cable itself and then the USB connector. The following programs are considered optimal for use: VAG-COM USB KKL adapter; VAZ diagnostic program for models, Priora, Kalina, Grant; USB driver Autocom cdp pro cars USB; ScanMaster 2.1 in Russian for ELM327.

Troubleshooting and reset

Eliminating ECU errors is quite simple. In the reading program, you need to find the desired fault and decipher it. Then, it is recommended to fix the problem that caused the error. The last step is reset. It can be found in program tools or actions.

Location of the connector for connecting to the ECU

Possible location of the connector for connecting to the ECU

Many car enthusiasts make a mistake when working with software, because they “reset” not the errors themselves, but the entire software, thus leaving only the car software shell. After such actions, usually, the car may not start and software adjustment of the equipment or replacement of the entire software as a whole is required. Therefore, in this case, it is recommended to contact a car service, where they will do everything correctly.

Error P0303 Lada – misfire in the third cylinder

Misfire detected in cylinder 3

Possible causes of the error in a Lada car: • The ignition coil of the third cylinder is faulty • The spark plug of the third cylinder is faulty • The injector of the third cylinder is clogged or faulty • The wiring of the ignition coil of the third cylinder is broken or shorted • The wiring of the injector of the third cylinder is broken or shorted • The wiring connector of the injector of the third cylinder is faulty • Malfunction of the ignition coil connector of the third cylinder • Incorrect fuel pressure • Low compression in the 3rd cylinder • Intake manifold air leak

Error code P0303 means that a misfire or random misfire has been detected in the third cylinder of the VAZ engine. It is better to carry out diagnostics in the following sequence - check the intake tract for air leaks, the next step is to replace the spark plug in the third cylinder. If the problem cannot be solved by these two points, then it is necessary to carry out additional diagnostics, which are described in detail here.

POSSIBLE SYMPTOMS OF ERROR P0303 VAZ

: • “CHEK ENGINE” signal is on; • Lack/loss of engine power; • The engine shakes. Uneven engine operation; • It is difficult to start the engine. Especially cold.

Description of error P0303 Lada If a misfire occurs, the engine speed will fluctuate. If changes in engine speed are sufficient to change the crankshaft position (CKP) sensor signal, the engine control module (ECM) detects the P0303 Lada .

ignition coil

The ignition coils have the following circuits: — Power circuit of the primary windings The voltage of the vehicle’s on-board network is supplied from the main relay (ignition relay) to contact “3” of the individual ignition coil. — Control circuit for the primary winding of the ignition coil The controller switches to ground the circuit of the primary winding of the ignition coil, which supplies high voltage to the spark plugs of the corresponding cylinders: contact “1” of the individual ignition coil.

ignition coil location

ECU controller location

P0300 - misfire error. Causes, consequences, elimination

Error code P0300 indicates a violation of the ignition order , which stands for random multiple misfires of the cylinders ; in English, the diagnostic tool displays: “Random cylinder misfire detection system.” If a misfire is detected in a specific cylinder, then the last digit “P030x” will change to 1, 2, 3, 4 and so on up to 6 or even 12, depending on which particular “pot” the misfire is in. So error P0300 is derived from errors such as P0301, P0302, P0303, P0304. Most often they occur due to a lack of spark, a fuel supply failure or problems with the exhaust gases.

Let's look at the list of possible causes of misfires, why error p0301, error p0302, error p0303, error p0304 or others of this kind appears, the consequences and methods of elimination, in more detail.

SELF-DIAGNOSTICS OF THE KALINA/PRIORA INSTRUMENT COMBINATION

1. With the ignition off, press the “Reset” button (reset daily mileage). While holding the button, turn on the ignition.
2. The instrument panel will go into self-diagnosis mode, all segment positions will light up on the display, all indicators will light up, and the arrows will travel the full path.
3. Using the control button on the right steering column switch, we switch between modes (self-diagnosis, firmware version, error codes).
4. To reset errors, you need to be in error mode and press and hold the “Reset” button for more than 3s.
5. The diagnostic mode exits automatically after inactivity for 20-30 seconds.

Decoding error codes in the dashboard:

• 2-increased voltage of the on-board network;
• 3-fuel level sensor error (if a break in the sensor circuit is detected within 20s);
• 4-error of the coolant temperature sensor (if an open circuit of the sensor is detected within 20s);
• 5-outside temperature sensor error (if there are no sensor readings within 20s, indication on the LCD is “-C”);
• 6-engine overheating (the criterion for triggering the acoustic alarm has been met);
• 7-emergency oil pressure (the criterion for triggering the acoustic alarm is met);
• 8-defect of the brake system (the criterion for triggering the acoustic alarm is met);
• The 9-battery is discharged (the criterion for triggering the acoustic alarm is met);
• E-determination of an error in a data packet stored in EEPROM.

Combination

Consequences of error P0300

If a misfire occurs in the engine in the exhaust pipe the level of exhaust gas toxicity increases , which, in turn, can also lead to an increase in the temperature in the catalyst, which causes its damage (the honeycombs melt because the temperature exceeds the threshold of 800 °C ). On some cars, in order to reduce the burnout of fuel in the catalytic converter and, consequently, the level of toxicity, the ECM unit monitors the frequency of misfires using crankshaft and camshaft sensors and, in addition, it registers error p0300, signaling a checkengine light can also , in which the gap was discovered. It is worth mentioning that most often, for some reason, the owners of cars such as Lacetti, Matiz, Priora and other injection VAZs, as well as Opel, Nissan, Kia cars, are interested in the reasons for the occurrence of this error.

When does error code P0300 pop up?

Note that error code P0300 is recorded by the control unit only when misfires are detected in several cylinders simultaneously , since a misfire in one of them is recorded after two repetitions in a row, and the rotation speed of the CV is important. At idle, the error is stored in memory after 3.5 minutes of engine operation, and at speeds above 2 thousand - a little more than one minute. threshold for registering a DTC in the ECM memory is more than 3.25% of missed flashes per 1000 revolutions. If misfires are detected only in a certain cylinder, then not error P0300 is generated, but another one, with the serial number of the combustion chamber of the internal combustion engine.

Rare cases of error p0300

On some vehicles of the VAZ family with an electronic on-board computer of the M74 series, errors p0300, p0301, p0302 may appear due to problems in the fuse connector. The connector body itself may appear completely sealed and show no external deformation when its contents fail. It is necessary to replace the connector with a new one to eliminate errors.

On older foreign cars, misfires in the cylinders may occur when the power unit is first started at a temperature below -10 degrees Celsius (or when the temperature of antifreeze/antifreeze in the expansion tank is below -10 degrees Celsius). This is due to the lack of adaptation of cars to Russian operating conditions. However, after the engine warms up, the error disappears.

Thus, the appearance of error code p0300 does not always indicate serious problems in the car’s ignition system. In each specific case, it is necessary to consider all possible options for the occurrence of an error. As stated above, engine misfire is considered one of the most serious problems, so it is necessary to quickly take action to accurately diagnose and eliminate the problem.

Error p0300, p0301, p0302, p0303 and p0304 causes

Unfortunately, the diagnostic tool has not learned to determine the specific cause of the failure and, in this case, misfire in the engine cylinder, but, fortunately, the most likely malfunctions can develop in two directions - either there is nothing to burn , or it is impossible to ignite . Although it is still too early to rejoice at the possible quick search for the cause of error p0300, since it could be:

Cylinder misfires. How to diagnose the cause.

1. In the ignition system

• spark plug failure;
• breakdown of a high-voltage wire;
• faulty ignition coil (or module);
• other reasons related to wiring and connectors in the ignition system.

• In the power system
• poor quality fuel;

clogged injectors;

• heavily contaminated fuel filter;
• low fuel pressure.

The main reasons why error P0300 occurs

If it is not a general problem of multiple misfires , but for a specific cylinder: p0301, p0302, p0303, p0304 or others, the situation is simplified and most likely lies in the ignition system . In such cases, error P0363 may also be displayed, but it also indicates that the fuel supply to the cylinder is blocked.

Common errors when diagnosing code P0303

The most common mistake when diagnosing a P0303 is failure to follow the diagnostic protocol. It is also a mistake to replace spark plugs, ignition coils, and related wires when the problem is an intake air leak or a malfunction of the fuel injection system. Before replacing any components, you must perform a thorough diagnosis and consider all possible causes of the error.

Recommendations for checking and troubleshooting

The first thing you should check when misfiring is the explosive wires and ignition coils (module), they often turn out to have broken insulation, a break, or an oily surface. We measure the wires with a multimeter (normal resistance is about 4 - 10 kOhm), in resistance mode, but to check individual ignition coils, you just need to swap places with a known working cylinder and clear the errors again. If the code has changed to the number of another cylinder, then the coil is faulty. The ignition module is more complicated; it needs to be checked with a tester.

Technical description and interpretation of error P0303

The OBD II error code P0303 is a generic one that reads “Cylinder #3 misfire detected.” Set when the PCM (powertrain control module) detects a misfire in the third cylinder.

The misfire detection system uses input data that is sent to the PCM through dedicated feedback circuits. If the PCM does not receive feedback, it interprets this as a misfire.

Trouble code P0303 indicates that the third cylinder is misfiring. They occur when insufficient fuel is burned in the cylinder. Efficient combustion of fuel is important. Because fuel combustion is the source of energy for engine operation.

Misfires can be caused by many reasons. Due to a faulty ignition system, fuel system or internal engine failure. Often the fault occurs due to worn spark plugs, spark plug wires or a faulty coil.

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Symptoms of malfunction

The main driver symptom of P0303 is the MIL (Malfunction Indicator Light) illumination. It is also called Check engine or simply “check light”.

They can also appear as:

1. The “Check engine” warning light on the control panel will light up (the code will be stored in the ECM memory as a malfunction).
2. The engine stalls or has trouble starting.
3. Floating speed, as well as attempts to stall at idle.
4. Jerking/misfire at idle or under load.
5. Poor speed gain.
6. Increased fuel consumption.
7. Reduced engine power.
8. Smell of fuel from the exhaust.

This malfunction is considered serious and must be corrected as soon as possible. Because prolonged driving with a misfire can cause costly damage to the engine and catalytic converters.

Reasons for the error

A P0303 code may mean that one or more of the following problems have occurred:

• Faulty or worn spark plugs.
• Worn or damaged ignition wires.
• Coil failure.
• The oxygen sensor is faulty.
• Damage to fuel injectors.
• Vacuum leak.
• Low fuel pressure.
• The camshaft position sensor is faulty.
• Malfunction of the crankshaft position sensor.
• Clogged pipes or valve of the exhaust gas recirculation system.
• Catalytic converters are clogged.
• The air flow sensor is faulty.
• Throttle position sensor malfunction.
• Leaking cylinder head gasket.
• Low engine compression.
• Poor quality fuel.
• Sometimes the cause is a faulty PCM.

Decoding error codes Lada Priora

Note! These encodings are also relevant for the Kalina version.

Exhaust (0000)

• 30 – break or damage to the oxygen sensor heater before the catalyst;
• 31 – same as 30 with short circuit to body ground;
• 32 – similar short circuit for on-board wiring;
• 36 – break in the wiring of the oxygen heater after the catalyst;
• 37 – wiring short to ground;
• 38 – open circuit from short circuit to BS.

Air supply failure (0101, etc.)

• 102 – open or damaged air flow sensor circuit;
• 103 – short circuit of the mass air flow sensor network;
• 112/13 – violation of the temperature indicators of the air mixture on the intake manifold;
• 115/16 - failure of antifreeze temperature sensors - the system does not cool, the main fan may not work correctly;
• 117 – open circuit of DTOZH;
• 118 – short circuit of the same sensor;
• 122/23 – violation of the throttle position sensor circuit;
• 130 – error DC 1;
• 131 – break in oxygen sensor 1;
• 132 – short circuit of DPKV 1 circuit;
• 133 – difficulty in response of the oxygen sensor (possible poor contact);
• 134 – break in the oxygen sensor line;
• 135 – failure of the heating device DK2;
• 136 – ground fault DK2;
• 137/138 – weak/high impulse of DC2;
• 140 – break in the DK2 highway;
• 141 – failure of heater DK2;
• 171/172 – excessively lean/rich air-fuel mixture.

Failure to supply fuel mixture (0200)

• 201-204 – break in the control line of injectors 1-4, respectively, characterized by engine tripping;
• 217 – internal combustion engine overheating;
• 230 – open circuit of the fuel pump control relay – the engine does not turn on or does not start;
• 263/266/269/272 – failure of the injector driver for cylinders 1-4, respectively;
• 261/267/270/264 – ground fault of injector lines from 1 to 4, respectively;
• 262/265/268/271 – short circuit at 12 V.

Ignition design violation (0300)

• 300 – no spark on all cylinders (large number of misfires);
• 301/302/303/304 – ignition interruptions in 1-4 boilers, respectively (ICE triples or doubles);
• 325 – DD break or failure;
• 327/328 – violation of knock sensor readings;
• 335/336 – violation of the DPKV operation;
• 337/338 – short circuit to ground or violation of the DPKV signal;
• 340 – DRF failure;
• 342/343 – violation of the phase distribution sensor signal;
• 346 – exceeding the tolerance of DRF indicators;
• 351-354 – the wiring of the ignition coils for cylinders 1-4 is interrupted, respectively;
• 363 – no supply of fuel and air to the cylinders.

Additional equipment control systems (0400)

• 422 – catalyst is clogged – urgent replacement or repair is required;
• 441 – violation of the adsorber purge valve;
• 443 – violation of the purge circuit;
• 444 – short circuit or break in the same network;
• 445 – also with short circuit to ground;
• 480/481 – violation of the integrity of the coolant fan wires.

Engine speed control violations (0500)

• 501/502 – incorrect reading of speed sensor indicators;
• 503 – DC is loose or short-circuited;
• 505 – malfunction of the XO regulator;
• 506 - engine idle speed is too low - when the load is removed, the engine stalls;
• 507 – the opposite value of the previous code, revolutions can also float;
• 511 – failure of the XX regulator network;
• 560/562/563 – problems with the on-board network voltage.

On-board network violations (0600)

• 601 – ROM failure;
• 603/604 – internal/external RAM malfunction;
• 607 – disorder of the detonation line;
• 615 – break in the wiring of the auxiliary starter relay;
• 616 – duplicates the previous problem with a short circuit to ground;
• 617 - the same, only with a contact for the on-board wiring;
• 627 – there is no power to the fuel pump, the wires may be interrupted;
• 628 – also with a break and a short circuit to the body;
• 629 – duplicates the previous cipher with a connection to the machine’s network;
• 645 – no power supply to the air conditioning compressor clutch relay;
• 646/7 – complements the above failure with a short circuit to the body or on-board wiring;
• 650 – the “Check Engine” lamp has burned out;
• 654 – failure in the electronic part of the tachometer;
• 685/6/7 – break in the main relay wire/with a short to the body/network;
• 691/692 – break in the main cooler control circuit/with a short to other wires.

Additional signals about the causes of the malfunction (1000)

• 102 – the DC heating resistance has disappeared;
• 115 – circuit failure of the same sensor;
• 123/124 - violation of mixture formation in the absence of load - idle is acting up;
• 127/128 – duplicates the previous signal in partial load mode – jerks, dips or jerks when pressing the gas pedal lightly;
• 135 – open circuit or short circuit of circuit DK1;
• 136/137 – violation of the formation of a combustible mixture at minimum load;
• 140 – potential difference between measured and actual load;
• 171/172 – incorrect operation of the potentiometer;
• 386 – incorrect detonation channel test result;
• 410/425/426 – short circuit to the sides or ground/break in the lines of the canister purge valve;
• 500/501/502 – open circuit with short circuit of the fuel pump for ground and 12V, respectively;
• 509 – overload of the XX regulator;
• 513/514 – short circuit of the throttle position in position XX;
• 541 – there is no power to the fuel pump or the integrity of the housing may be damaged with fuel getting inside;
• 570 – an incorrect signal from the APS design is received;
• 600 – no impulse is received from the APS; there may be a breakdown or the unit is coming off;
• 602 – 12V short circuit to the electronic engine control unit;
• 603 – problems with the firmware, can be resolved by rebooting;
• 606/616 – interruptions in the operation of the rough road sensor;
• 612 – incorrect ECU reset code – the system did not reboot;
• 617 – the rough road sensor has died or a short circuit has formed;
• 620 – critical fault in the EEPROM;
• 621 – critical RAM fault;
• 622 – failure or breakdown of the EEPROM;
• 640 – conflict in checking firmware status;
• 689 - diagnostics showed that all vehicle systems are in order - erroneous codes were displayed.

How to Troubleshoot or Reset Trouble Code P0303

Some suggested steps to troubleshoot and fix error code P00303:

1. Use an OBD scanner to make sure there are no other errors. If they are present, it is recommended to eliminate them first.
2. Inspect the looseness of the connectors on the ignition coils or any damage to the wiring. Also look for loose engine ground wires. This may cause random misfires. Tighten or correct if necessary.
3. Check the condition of the spark plugs and their wires. Worn and old spark plug wires are common causes of random misfires. Replace spark plugs and wires if necessary.
4. It is necessary to measure the fuel pressure. Low pressure can cause intermittent misfire in multiple cylinders. When the pressure is below specification, the engine does not receive the proper amount of fuel and begins to lean the mixture. The fuel pump or pressure regulator may be the source of low pressure.
5. Make sure the fuel injectors are working properly and activating. Random misfires may be a sign of faulty or clogged fuel injectors that need to be replaced. Also check that the fuel injector wiring is not damaged and is connected correctly.
6. If the ignition and fuel system pass inspection, you can perform an engine compression test and a leak test to see if there are any mechanical problems causing the misfire.

Diagnosis and problem solving

Sometimes, when P0303 is detected, no symptoms are observed. The easiest thing to do in this case is just reset the code and see if it comes back.

If the problem manifests itself in the form of uneven idle or engine jerking, check all wiring and connectors leading to the cylinders. Next, it’s worth checking the spark plugs, wires, and coils.

In some cases, the cause is a failed catalytic converter. If you smell a rotten egg smell in your exhaust, the catalytic converter needs to be replaced. Faulty fuel injectors should also not be overlooked.

Random misfires may be due to lean fuel. This may be due to a vacuum leak in the intake manifold or air flowing past the airflow sensor. And also because of the exhaust gas recirculation valve stuck in the open position.

Possible causes of the P0300 error code

Let us once again remember the saying about “there is nothing to set on fire and nothing to set on fire with.” This is where the list of possible faults comes from.

1. These are old and dirty spark plugs that, due to carbon deposits or destruction of the electrodes, misfire. This is easy to check - by turning out the spark plugs and, to be on the safe side, replacing them with a new and known good set.
2. This is a malfunction of the ignition coil itself or the distributor on old engines with central ignition (for example, the Japanese had distributor injection engines that survived almost until the two thousandth century). More modern engines with individual ignition coils or paired coils (separate, as on ZMZ engines, or interlocked, as in VAZ ignition modules) in this case, problems will arise only with a specific cylinder or with a pair of cylinders, that is, error P0300 will not be recorded.
3. “Nothing to set on fire” may also be due to insufficient compression in the cylinders or incorrect operation of the gas distribution. The first is checked with a basic compression tester, or in a car service - with a motor tester. Measuring intake vacuum and cylinder pressure directly while the engine is running gives a much more accurate picture of the engine's condition.
4. Incorrect operation of the gas distribution mechanism is, first of all, the “loss” of marks due to a stretched timing chain, a skipped belt, or assembly errors of “keyless” engines, where there are no marks at all, and the shafts are set with special devices. A classic example is Ford keyless engines, where a deviation of several degrees can already cause tripping at idle and the recording of numerous misfires.
5. The air-fuel mixture may also refuse to ignite normally due to an incorrect composition. A mixture that is too lean is ignited with a candle “every other time,” while a mixture that is too rich will cause the candles to become fouled with soot. A characteristic sign of this is the presence in the controller’s memory of errors in the composition of the mixture (P0172, P0171), or at least a fuel correction noticeably different from zero. We only note that chaotic misfires on engines with plastic intake manifolds are most often caused by warping or cracking of the plastic and the occurrence of an error. Neither “basins” nor foreign cars are immune from this.
6. There is another way to make the engine stall, and it works best at idle, when engine vibration is more noticeable and crankshaft accelerations are calculated more accurately: a malfunction of the exhaust gas recirculation system. On engines with EGR, the supply of exhaust gases to the intake is controlled by an electric valve, the throughput of which is determined for each specific mode by firmware. An abnormal supply of exhaust gases literally “chokes” the engine, forcing it to work intermittently - hence the recording of error P0300. In this case, there will be associated errors associated with the operation of the EGR, and physical suppression of the exhaust gas supply channel will lead to a noticeable normalization of engine operation.
7. And finally, let’s not forget about the “quality” of gasoline itself: we have repeatedly encountered liquid in gas tanks that only vaguely resembles flammable liquid. It doesn’t have to be a “palenka” - often the culprit is the gas station attendants, who regularly manage to pour diesel fuel into the gasoline, and gasoline into the diesel fuel.

Which of the following is easier to do without contacting the service?

At a minimum, check the spark plugs, compression, and fuel pressure. Spraying the joints of the intake manifold parts with a spray such as WD-40 will help locate the leaking area. The performance of the injectors and the shape of their spray pattern is checked by cranking the engine with the starter with the ramp pulled out (ATTENTION! Fine gasoline sprayed by the injectors is extremely fire hazardous!). Timing timing marks on most engines are also easy to check.

Is it possible to drive with P0300?

Definitely not worth it. Do not forget that misfire diagnostics were introduced to save the catalyst. The already dubious pleasure of driving with a shaking engine can be supplemented by caking or destruction of the catalyst.

In addition, this may indicate a malfunction of the engine: “creeped” timing marks may subsequently result in the pistons meeting the valves, and this is a serious and expensive repair.

On which cars is this problem most common?

The problem with code P0303 can occur on different machines, but there are always statistics on which brands this error occurs more often. Here is a list of some of them:

• Audi (Audi a4, Audi a6)
• BMW (BMW E46)
• Chery (Chery Tiggo)
• Chevrolet (Chevrolet Aveo, Cruz, Orlando, Trailblazer)
• Chrysler (Chrysler Voyager, PT Cruiser)
• Dacia (Dacia Largus)
• Daewoo (Daewoo Gentra, Nexia)
• Dodge (Dodge Caravan, Stratus)
• Fiat
• Ford (Ford Windstar, Mondeo, Fiesta, Figo, Focus, Fusion)
• Honda (Honda Accord, Civic)
• Hyundai (Hyundai Accent, Getz, Santa Fe, Solaris, Tucson, Elantra)
• Infiniti
• Jeep (Jeep Grand Cherokee, Liberty)
• Kia (Kia Rio, Sid, Sportage)
• Lexus (Lexus rx300)
• Mazda (Mazda 3, Mazda 6, Mazda cx7, Tribute, MPV)
• Mercedes
• Mitsubishi (Mitsubishi Galant, Lancer, Space Star, L200)
• Nissan (Nissan Almera, Qashqai, Terrano)
• Opel (Opel Astra, Vectra, Zafira, Corsa, Meriva)
• Peugeot (Peugeot 307, 308)
• Renault (Renault Duster, Logan, Sandero)
• Skoda (Skoda Yeti, Octavia, Fabia)
• Ssangyong
• Subaru (Subaru Outback, Forester)
• Suzuki (Suzuki Grand Vitara)
• Toyota (Toyota Camry, Corolla, Prius, Fielder)
• Volkswagen (Volkswagen Golf, Jetta, Caddy, Passat, Polo Sedan, Touareg, Tiguan)
• Volvo
• VAZ 2110, 2112, 2114, 2115
• Volga Cyber
• Gazelle Business
• Lada Kalina, Largus, Niva, Priora
• UAZ Patriot

With fault code P0303, you can sometimes encounter other errors. The most common ones are: P0016, P0102, P0113, P0171, P0174, P0183, P0203, P0267, P0300, P0301, P0302, P0304, P0305, P0306, P0316, P0363, P0400, P0420, P1303.

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