On a VAZ 2115, it starts perfectly when cold, but when starting hot, it immediately stalls. After it cools down, it starts without problems. What could be the reason?
Poor hot starting is one of the diseases of VAZ cars. Therefore, the question is very common. This happens due to the low quality of spare parts and some design features. It happens that the fuel pump is replaced with a new one, but it turns out to be faulty. “In search of a malfunction” everything is changed, and the problem is revealed already on the second round.
If the car does not start when hot, we recommend checking using the following algorithm:
- Point for beginners. Make sure that the problem is related to the “hot” state of the car. Check the battery charge, make sure that the generator is charging (with a multimeter in voltmeter mode). Are there any problems with the starter? If it sometimes turns, sometimes it doesn’t, or occasionally turns poorly, take it to an electrician.
- For everyone else. It is advisable to start repairs with diagnostics - it can help save money. A diagnostician will reveal approximately 80% of the causes of the problem, the faulty part will be replaced, and the car will drive and make you happy.
The rest of the information is for the remaining 20% (diagnostics does not reveal problems) and those who do not have qualified specialists in the access area.
Impact of sensors
Most VAZ-2115 cars operate on the “January 5.1” controller. Crankshaft, temperature and throttle sensors are involved in starting the engine.
DPKV malfunctions usually appear regardless of temperature, but it is worth checking its resistance and comparing it with the data in the calibration table.
A more common malfunction is DT . Remove from position and place in a container with a cooler. We measure the resistance with a multimeter: it should be in the region of 1350 - 1880 Ohms. If you have a thermometer, you can check it using the table. If not, it doesn’t matter either, just heat it to an arbitrary temperature. As T increases, the resistance decreases. On a fully warmed up engine it is 87 - 109 Ohms. If the ohms do not change or drop to 0, change the DT.
The throttle assembly is completely disassembled and cleaned. One of the problems is dirt, which expands when heated and interferes with the normal operation of the injection. If the TPS , the car not only does not start when hot, but also “does not drive” (sometimes stalls and does not start) after warming up.
The TPS is checked with an ohmmeter with the engine running. Place the multimeter on the input and output contacts, ask an assistant to press the gas. The readings should change and return to their original values at XX. If the resistance does not change when you press the pedal or the device shows infinity, the sensor needs to be replaced. At the same time we check the IAC. It usually causes the car to be unstable at idle or stall but start.
A malfunction of the mass air flow sensor on cars with January 5.1 is recognized by the fact that the car starts when hot and immediately stalls. The sensor comes into operation only after startup. But on a car with January 7.2, the mass air flow sensor is involved in the start - without it the car will not start.
Fuel pump and related
The first malfunction is insufficient pressure in the fuel rail. During operation, the pump heats up and begins to pump poorly. Because of this, the car may stall and not start.
The pressure is checked by installing a pressure gauge. At idle in the system 2.5 atm, in power modes it should increase to 3. With a faulty pump, these indicators may differ between a cold and hot engine. Check in the mode in which problems arise.
One of the problems of the VAZ 2115 is the bypass valve, which, if faulty, begins to “let in” fuel on a heated engine. Bottom line: fuel pressure drops and takes time to build up. Symptoms are a long period of production or its complete absence.
Another reason for a drop in pressure in the system may be a clogged fuel filter or strainer in the tank. When heated, dirt expands and clogs the fuel flow.
Fuel supply problems
In injection engines, the fuel supply system is slightly different from the system installed on carburetors. Gasoline is supplied from an electric pump with a built-in filter. The filter is not changed on time, there is insufficient fuel supply, which means there will be difficulties with starting and normal operation of the engine. It also wouldn’t hurt to check the fuel pressure in the line and the operation of the injectors.
Engine starting problems in injection systems can also occur due to a malfunction of the fuel pressure regulator. It is impossible to exclude such a trivial problem as an air leak in the power system; it makes it very difficult to start a cold engine. Pay attention to the fuel poured into the tank; its quality also greatly affects engine starting.
Ignition module
Another problem is the ignition module. This malfunction was more common on cars of the Samara-1 generation. In the case of Samara-2, the quality of the part itself has improved, but the root of the problem remains. The module is attached to the cylinder block, which causes it to get very hot and burn out the windings. As a result, when hot, it is possible to lose spark in one, several or all cylinders at once.
If the car does not start when hot, check the spark. If it doesn't, that's almost certainly the problem. You can usually resolve the issue by replacing the module, but if the problem returns, consider moving the bracket to another location. Most often it is installed in the front part of the engine compartment, near the radiator.
Most problems with poor engine starting when hot are solved using these methods. But less probable ones are also possible: broken wiring, ECU malfunction, etc.
General faults
It is necessary to distinguish between situations when the car simply cannot start, and when the VAZ 2114 does not start when it is hot. In the first case, the reasons may not be related specifically to a warm engine.
The most common faults include:
- The battery is low - the charge level is not enough to start the car again.
- Problems with the starter - its speed drops, or the relay needs to be changed.
- Poor quality fuel - as a result of using gasoline with impurities, fuel system valves or injectors may become clogged.
Important! If black or white residue accumulates on the spark plugs, there may be problems with the ignition system, fuel system filters, or fuel pump. Therefore, when a plaque is detected, the car needs diagnostics.
Another common reason that the engine does not start, either hot or cold, is problems with the ignition module. This is due to a design solution - the ignition system module is attached to the car’s cylinder block. If the windings get too hot, they may burn out. As a result, the spark does not reach one or several cylinders at once.
To check the serviceability of the VAZ 2114 ignition system, you need to:
- Check the sparks on the spark plugs - the absence of a spark on several spark plugs at once can cause problems with starting the engine, and indicates a problem with the operation of the module.
- Inspect the high-voltage wires - if there is no spark on one spark plug, this indicates a possible wire break. Therefore, it is necessary to inspect the wires for mechanical damage.
The car doesn’t start well when it’s hot: we look for and fix the problem
Modern cars are gradually moving from the concept of mechanisms to the concept of organisms. This is a highly complex system that requires ideal operating conditions. High engine power, squeezing everything that can be squeezed out of technology, and other features of the modern automobile industry indicate that modern cars must receive maximum care in order to work for a long time. One of the common problems that arise from improper car care is poor engine starting after it warms up. This means that if you park for a few minutes near the store, you will not be able to start the engine properly. The problem lies in two possible types of breakdowns, but there are also extraordinary cases. Today we will deal with the most common problems in this case, and also talk about specific types of problems.
It should be noted that the symptoms of poor hot starting can manifest themselves in different ways. One car refuses to start at all until the engine cools down a certain amount. Another power unit starts only on the third or fourth try, and the third one simply has to be cranked for a long time to start. In any case, no matter what happens to your car in this context, you need to find the problem and be sure to fix it. This task is a harbinger of more serious breakdowns, the repair of which will cost you much more money. So let's figure out why the car doesn't start well when it's hot.
Bad fuel or presence of additives in the fuel mixture
Low-quality gasoline or diesel fuel is one of the most common variants of this problem. But in this case, you can conduct an experiment that will show the true problem of your car. The fact is that low-quality fuel with a poor start when hot will have an even more unpleasant effect when starting the engine when cold. Therefore, it is enough to cool the car, wait for the engine to return to normal and start it. The following problems may also occur with fuel:
- Gasoline or diesel fuel may contain an additive that your engine does not accept;
- diesel fuel has frozen and acquired a jelly-like form, which is difficult to pump;
- there are solid particles in gasoline, the filters are clogged, and it is difficult for the pump to pump the required amount of fuel;
- the settings of the engine control system and air supply have gone wrong, one of the valves may have broken;
- the idle air valve, as well as the mass air flow sensor (mass air flow sensor) can cause such problems;
- It’s just a functional feature of carburetor engines - a very hot unit has difficulty starting.
In the case of carburetor units, everything is quite simple - the engine itself starts very poorly when hot. This is due to the fact that after stopping the car with a hot engine, the temperature in the carburetor area is quite high. Under the influence of temperature, gasoline quickly evaporates and fills all chambers and tubes of the carburetor in a gas state. But the float chamber remains empty. If you decide to start the engine within five minutes of stopping it, you will encounter difficulty starting because there is no liquid fuel in the chambers. The problem can be solved by manual pumping or several attempts to start the power unit. However, there cannot be such a problem with injectors, since the fuel is supplied directly from the main line. Therefore, it is worth looking for other troubles in the fuel supply system.
Too rich or lean mixture - air flow sensor
We mentioned above that problems with starting a car can occur due to the failure of the mass air flow sensor. This element of the car is one of the most sensitive to environmental influences, so they often talk about its breakdown. If starting the engine when hot is very difficult, check the functionality of this mechanism. The following factors may also accompany this failure:
- failures when pressing the gas pedal, lack of traction at some moments;
- a decrease in power or vice versa - an inexplicable increase in the operating potential of the unit;
- complication of engine starting and periodic moments of choking;
- explosions inside the exhaust system when the gas pedal is sharply pressed;
- unstable speed due to periodic changes in mixture enrichment.
The fuel mixture of gasoline and air must have a certain consistency, which is formed by the mass air flow sensors and some other parts of the electrical and electronic system of your car. If these parts are faulty, you will have to change them and test the car, set up the operation of the new equipment.
This is interesting: Setting up the carburetor on a scooter
The fuel pump has overheated - a common problem in domestic cars.
The fuel pump cools naturally by pumping cool liquid from the fuel tank. But in extreme heat, this liquid cannot be cool in any way, so the fuel pump overheats. This is an unpleasant incident that can lead to the impossibility of starting the car when it is hot. The car may simply stall on the road and not start either with a pushrod or by starting it by turning the ignition key. There are several ways to fix this problem:
- take a wet and cold rag, apply it to the fuel pump and periodically moisten it with cold water, cooling it;
- open the hood and place the car in the shade, allow all parts of the power unit to cool normally;
- change the fuel pump if you have the opportunity to quickly obtain another part of the fuel system;
- just wait until the temperature of the fuel pump returns to normal and continue operating the car;
- An overheated fuel pump is unlikely to work normally, so it’s better to just change it.
This problem can cause the failure of important parts of the fuel pump, because when it overheats, it stops working for a reason. If after cooling the car nothing changes, then you will have to replace the fuel pump. But usually the car starts when cold, and then drives for several days without any problems.
Problems with poor starting of gas cars in warm weather
Many drivers, having read all the above arguments, will say that they are not valid for their car, since it has a gas installation. It became profitable to drive on gas several years ago, so LPG has found its way under the hood of many car enthusiasts. If in hot weather your car stalls and does not start when hot, you will have to let it cool completely, then start it and go straight to the service station. It’s better not to joke with this question for a number of reasons:
- due to high temperatures, certain seals could deteriorate and gas hoses could open;
- the working fluid of your car’s fuel system may leak for other reasons;
- expansion of gas in the tank at high temperature creates a certain pressure in the system;
- It is better not to fill a full gas tank in hot weather, limiting yourself to partial refueling;
- It makes sense to consult with a specialist if such a problem begins to occur on your car.
You shouldn’t joke with gas-powered cars at all - even the latest generation of LPG carries a certain danger. If your gas car does not start when hot, it is worth hiring a specialist to solve this problem. This way, you can easily obtain the necessary operating features of the power unit, and you will not expose yourself to the danger of incorrect operation of the fuel supply system. We invite you to look at the experts’ explanations about a poor launch during the busy season:
Let's sum it up
High-quality fuel supply systems rarely fail, so even in the hottest weather, hot cars start without problems. But if such a problem occurs, the driver is unlikely to be able to fix it on his own. There are too many factors of possible breakdowns that are difficult to check without special knowledge and certain tools. Therefore, it is best to show the car to specialists and get a very specific answer to your problem. Most likely, repairing this problem will involve minor sensor replacements and not too expensive procedures.
Therefore, in most cases, turning to the experts will be the key to a successful trip in your car in any weather. You need to contact a service station as soon as signs of poor car starting begin to appear in your case. The sooner you come to the master, the easier it will be for him to help you. And the cost of repairs increases when the visit to the repairman is delayed. Have you ever had a similar situation while driving a car?
What else affects engine starting?
The smart hardware of this model, which requires a lot of effort to start the engine, may also be to blame. Let's try to figure this out. One of the “problems” may be the crankshaft position sensor. The controller controls the injectors and ignition system using its own signals. Malfunctions of this device prevent normal startup.
Another similar source of difficulty. the most expensive of the sensors. mass air flow . According to his testimony, the control unit creates an air-fuel mixture. This is easy to check; just turn off and check the engine. If the problem goes away, the sensor needs to be replaced.
Carburetor engines have difficulty starting due to clogged carburetor jets (try bleeding). It is known that the injector does not have a carburetor, but the throttle body can create similar problems. This is especially true for engines with high mileage. Flushing with carburetor cleaning fluid solves these problems.
The temperature sensor informs the on-board computer about the condition of the coolant. If in carburetor engines it does not affect engine starting, then in our case its performance is recorded by a computer, and it forms the composition of the working mixture to supply it to the combustion chamber. If it fails, starting a warm engine will be very difficult.
To more accurately identify faults, specialists use special equipment that accurately identifies the faulty unit. It has been said about why the 8-valve injector of the VAZ 2114 does not start well, but at the end I want to give one more piece of advice. Look under the hood of your car often. This will allow you to notice poor connections, air leaks, and other minor problems and save you from unnecessary worries.
Why is the VAZ 2114 8-valve injector difficult to start?
For some reason, it seems that many drivers of this model will be interested in the question of why the VAZ 2114 8-valve injector does not start well. Finding the cause of this phenomenon is not as easy as it might seem at first. This is due to certain difficulties in troubleshooting in this model, since injection systems differ from carburetor systems. The algorithm for identifying possible problems will be built differently, adapting to the design features of the machine.
Why is the VAZ 2114 8-valve injector difficult to start?
, we will try to consider in this work. In a short article it is impossible to consider absolutely all possible problems; there are some that can only be identified with the help of diagnostic equipment. But, nevertheless, we will try to analyze as many such situations as possible in order to help all VAZ 2114 owners decide what to do in such a situation.
Why might the engine be difficult to start?
You can look for the culprit in such a situation in several directions. Among them, the most important problems are:
- Malfunctions in the ignition of a VAZ 2114 car
- There is no pressure in the fuel rail of the 8-cl VAZ engine
- Air leak into the VAZ intake manifold
- Timing belt marks are misaligned
Engine diagnostics using spark plugs
Let's look at the first option, why the VAZ 2114 doesn't start well. To do this, unscrew the candles and look at their color. If there is black dry carbon on the candles, we can say that the engine has been running for a long time on a rich mixture, which covers the candles with black carbon.
Why does black carbon appear on the spark plugs of an injection car:
- Malfunction of the mass air flow sensor
- The first oxygen sensor has failed
- Fuel pressure regulator is faulty
- Malfunction of fuel injectors
White carbon deposits on the spark plugs of an injection car appear due to a lean mixture, the reasons for the appearance:
- Everything is the same as with black soot
- Malfunction of the fuel pump or clogged fuel filter (check the mesh and fine filter)
- Air leaks through the air flow sensor pipe, the place where the regulator is attached to the XX joints of the manifold.
Checking the spark plug spark
The lack of a spark on one 8-cl spark plug of a VAZ engine will not affect the engine starting, it will be noticeable when idling, tripping and jumping revs. But if the ignition module of the VAZ 2114 is faulty, then the spark disappears in two cylinders 1-4 or 2-3. To check the spark plug spark, take out the fuel pump fuse, unscrew one spark plug or take a spare one, remove the high-voltage wires one by one, put them on the spark plug, then put the whole thing on ground (in this case, the valve cover) and ask a friend to crank the engine with the starter, so we check each spark plug. If there is no spark on one spark plug, most likely there is a defect in the explosive wires; if there is a spark in two or all spark plugs, it is highly likely that the problem is in the ignition module or the wiring to it.
The timing marks on the VAZ are not set correctly
Another reason why the VAZ 2114 does not start may be a mismatch of the timing marks. The reason for the mismatch of the marks may be weak timing belt tension, cut teeth, or the crooked hands of a mechanic at a service station.
A discrepancy of more than two teeth will noticeably affect the operation of the engine of the fourteenth. With a slight deviation, the engine starts up a little worse, does not hold idle, and stalls when switching to neutral gear. If the deviation exceeds 4-5 teeth, the sound of the engine changes, air escaping under pressure through the valves that are not opened in time becomes audible, thrust noticeably disappears, and starting the engine is extremely problematic.
- To check, we need a “10” key; use it to unscrew the three bolts securing the timing case.
- Next, put the car in 5th gear and push it until the mark on the camshaft pulley and the rear cover match, you can also turn the pulley with the key to “17”
- We remove the protective plug from the clutch housing and see if the mark on the flywheel matches the mark; if not, then you need to loosen the tension roller and align the belt according to the marks.
Checking the crankshaft sensor VAZ 2114
Perhaps this is the only sensor without which a VAZ car will not be able to start at all. If, when the engine is cranked with the starter and the ignition and fuel supply are working properly, there is no seizure or ignition of the fuel, then the problem is in the DPKV. The cost of the sensor does not exceed 300 rubles; it is better to replace it. However, there is a way to check: checking the crankshaft sensor video
If after the performed operations it was not possible to determine the breakdown, please write your problem in the comments, I will be happy to answer your question!
The VAZ 2114 car does not start when hot, but when driving everything is fine
The VAZ 2114 car does not start when hot, but when driving everything is fine. And so you can start it with a push. Who knows where to dig. The spark plugs were also replaced with wires. I have a video on my page, check it out.
26 comments on “The VAZ 2114 car does not start when hot, but when driving everything is fine”
Ignition module! Try removing it while it's hot and cooling it down.
I also had the same bullshit, the timing marks were knocked off
Check the crankshaft sensor
Possibly the ignition switch.
try putting a cold rag on it
Engine, fuel pressure
The bushing (copper) in the bell box is already broken and the starter (when hot) stupidly bites. This is only if everything is fine when cold.
Antokha, it’s normal to start when cold
Are the injectors not overfilling? try to drain the fuel from the ramp and start
Measure the compression and check the timing belt
Miras, you are 100% retractable. Last summer the same thing happened at 4. It won't start until it cools down a bit, right? If you change it, it costs around 500 rubles. This is the reason.
This is interesting: How to install a window regulator on a VAZ 2107
I had the same thing, only the reason was the fuel pump, I replaced it and everything became fine
The coins in the retractor get stuck, remove and clean or a new retractor!
Andrey, that’s right, what is this, can you send a photo?
Miras, here it is, I couldn’t take it off myself. There seems to be no way out without removing the starter itself. I tinkered with it for about an hour and a half and took it to the service center.
Here with the starter it’s... First, take it apart, look, you shouldn’t change everything because of this.
what kind of starter are you talking about? the starter turns
The fuel pump does not create the required pressure, it looks like check it
See crankshaft sensor
Akum. It was exactly the same bullshit. I spent 2 months looking for the problem, replaced everything, but it turned out to be the battery. changed the battery and everything is great
What does this have to do with the drawback, why are you hammering the kid’s brains. The starter turns the engine, you can hear it perfectly
disgraces, the girl is smarter than the boys. Not a shame, huh?
see tags. the sound of the belt came off
Look at the sensor that is located on the thermostat, it is temperature, but it is also responsible for the rich and lean mixture of fuel, I suffered for a long time, and changed 3 pieces (there are enough defects) by the sound, the first time it seemed to grab, this is exactly the same sensor. if the belt had come off, the sound would have been different, because... some valves are open, the starter would turn more easily, as if there was no pressure. For the sake of testing, try to remove the chip from that sensor while it’s hot and turn the starter longer, it will start.
