phase regulator breakdown

breakdown of the phase regulator may be as follows: it starts to make unpleasant cracking sounds, freezes in one of the extreme positions, the operation of the phase regulator solenoid valve is disrupted, an error is formed in the computer memory.

Although you can drive with a faulty phase regulator, you need to understand that the internal combustion engine will not work in the optimal mode. This will affect the fuel consumption and the dynamic characteristics of the internal combustion engine. Depending on the problem that has arisen with the clutch, valve or phase regulator system as a whole, the symptoms of a breakdown and the possibility of their elimination will differ.

The principle of operation of the phase regulator

in order to figure out why the phase regulator is cracking or its valve is sticking, it is worth understanding the principle of operation of the entire system. This will give a better understanding of breakdowns and further actions to repair them.

At different speeds, the internal combustion engine does not work the same way. For idle and low speeds, the so-called "narrow phases" are characteristic, at which the exhaust gas removal rate is low. Conversely, high speeds are characterized by "wide phases", when the volume of gases released is large. If “wide phases” are used at low speeds, then the exhaust gases will mix with the newly incoming ones, which will lead to a decrease in the power of the internal combustion engine, and even to stop it. And when “narrow phases” are turned on at high speeds, it will lead to a decrease in engine power and its dynamics.

Changing the phases from “narrow” to “wide” allows you to increase the power of the internal combustion engine and increase its efficiency by closing and opening the valves at different angles. This is the basic task of the phase regulator.

There are several types of phase regulator systems. VVT (Variable Valve Timing), developed by Volkswagen, CVVT - used by Kia and Hyindai, VVT-i - used by Toyota and VTC - installed on Honda engines, VCP - Renault phase shifters, Vanos / Double Vanos - a system used in BMW. further we will consider the principle of operation of the phase regulator using the example of a Renault Megan 2 car with a 16-valve ICE K4M, since its failure is a “childhood disease” of this car and its owners most often encounter an inoperative phase regulator.

The control takes place through a solenoid valve, the oil supply to which is regulated by electronic signals with a discrete frequency of 0 or 250 Hz. This whole process is controlled by an electronic control unit based on signals from the internal combustion engine sensors. The phase regulator is switched on with an increasing load on the internal combustion engine (rpm value from 1500 to 4300 rpm) when the following conditions are met:

• serviceable crankshaft position sensors (DPKV) and camshafts (DPRV);
• there are no breakdowns in the fuel injection system;
• the threshold value of phase injection is observed;
• coolant temperature is within +10°…+120°С;
• elevated engine oil temperature.

The return of the phase regulator to its original position occurs when the speed decreases under the same conditions, but with the difference that a zero phase difference is calculated. In this case, the locking plunger blocks the mechanism. so, the “culprits” of a breakdown of the phase regulator can be not only himself, but also the solenoid valve, internal combustion engine sensors, breakdowns in the motor, malfunctions of the computer.

Signs of a broken phase regulator

The complete or partial failure of the phase regulator can be judged by the following signs:

• Increasing the noise of the internal combustion engine. Repeating clanging sounds will come from the camshaft installation area. Some drivers say that they are similar to the operation of a diesel engine.
• Unstable operation of the internal combustion engine in one of the modes. The motor can keep idle well, but accelerate badly and lose power. Or vice versa, it’s normal to drive, but “choke” at idle. On the face of a general decrease in output power.
• Increased fuel consumption. Again, in some mode of operation of the motor. It is advisable to check the fuel consumption in dynamics using the on-board computer or a diagnostic tool.
• Increased toxicity of exhaust gases. Usually their number becomes larger, and they acquire a sharper, fuel-like smell than before.
• Increased engine oil consumption. It may begin to actively burn out (its level in the crankcase decreases) or lose its operational properties.
• Unstable rpm after engine start. This usually lasts about 2-10 seconds. At the same time, the crackle from the phase regulator is stronger, and then it subsides a little.
• Formation of an error of misalignment of the crankshaft and camshafts or the position of the camshaft. Different machines may have different codes. For example, for Renault, an error with code DF080 directly indicates problems with the Fazi. Other machines often get error p0011 or p0016, indicating that the system is out of sync.

It is most convenient to carry out diagnostics, decipher errors, and also reset them with a multi-brand autoscanner. One of these available options is Rokodil ScanX Pro. They can take sensor readings from most cars from 1994 onwards. pressing a couple of buttons. And also check the operation of the sensor by enabling / disabling various functions.

Please note that in addition to this, when the phase regulator fails, only a part of the indicated symptoms may appear or they appear differently on different machines.

Causes of failure of the phase regulator

breakdowns are divided precisely by the phase regulator and by its control valve. So, the reasons for the breakdown of the phase regulator are:

• Rotary mechanism wear (paddles/paddles). Under normal conditions, this happens for natural reasons, and it is recommended to change the phase regulators every 100 ... 200 thousand kilometers. Contaminated or low-quality oil can accelerate wear.
• See also or mismatch of the set values ​​of the turning angles of the phase regulator. This usually happens due to the fact that the rotary mechanism of the phase regulator in its housing exceeds the permissible rotation angles due to metal wear.

But the reasons for the breakdown of the vvt valve are different.

• Failure of the phase regulator valve seal. For Renault Megan 2 cars, the phase regulator valve is installed in a recess in the front of the internal combustion engine, where there is a lot of dirt. Accordingly, if the stuffing box loses its tightness, then dust and dirt from the outside mixes with the oil and enters the working cavity of the mechanism. As a result, valve jamming and wear of the rotary mechanism of the regulator itself.
• Problems with the electrical circuit of the valve. This may be its breakage, damage to the contact, damage to the insulation, short circuit to the case or to the power wire, decrease or increase in resistance.
• Ingress of plastic chips. On phase regulators, the blades are often made of plastic. As they wear out, they change their geometry and fall out of the seat. Together with the oil, they enter the valve, disintegrate and are crushed. This can result in either incomplete stroke of the valve stem or even complete jamming of the stem.

Also, the reasons for the failure of the phase regulator may lie in the failure of other related elements:

• Incorrect signals from DPKV and / or DPRV. This may be due both to problems with the indicated sensors, and to the fact that the phase regulator has worn out, due to which the camshaft or crankshaft is in a position that goes beyond the permissible limits at a particular point in time. In this case, together with the phase regulator, you need to check the crankshaft position sensor and check the DPRV.
• ECU problems. In rare cases, a software failure occurs in the electronic control unit, and even with all the correct data, it starts to give errors, including in relation to the phase regulator.

Dismantling and cleaning the phase regulator

Checking the operation of the fazik can be done without dismantling. But to perform a check on the wear of the phase regulator, it must be removed and disassembled. in order to find where it is, you need to navigate along the front edge of the camshaft. Depending on the design of the motor, the dismantling of the phase regulator itself will differ. However, be that as it may, a timing belt is thrown through its casing. Therefore, you need to provide access to the belt, and the belt itself must be removed.

After disconnecting the valve, always check the condition of the filter mesh. If it is dirty, it needs to be cleaned (washed with a cleaner). in order to clean the mesh, you need to carefully push it apart in the place of snapping and dismantle it from the seat. The mesh can be washed in gasoline or other cleaning liquid using a toothbrush or other non-rigid object.

The phase regulator valve itself can also be cleaned of oil and carbon deposits (both outside and inside, if its design allows it) using a carb cleaner. If the valve is clean, then you can proceed to check it.

How to check the phase regulator

There is one simple method for checking whether the phase regulator in the internal combustion engine is working or not. For this, only two thin wires about one and a half meters long are needed. The essence of the check is as follows:

• Remove the plug from the connector of the oil supply valve to the phase regulator and connect the prepared wiring there.
• The other end of one of the wires must be connected to one of the battery terminals (polarity is not important in this case).
• Leave the other end of the second wire in limbo for now.
• Start the engine cold and leave it to idle. It is important that the oil in the engine is cool!
• Connect the end of the second wire to the second battery terminal.
• If the internal combustion engine after that begins to "choke", then the phase regulator is working, otherwise - no!

The solenoid valve of the phase regulator must be checked according to the following algorithm:

• Having selected the resistance measurement mode on the tester, measure it between the valve terminals. If we focus on the data of the Megan 2 manual, then at an air temperature of + 20 ° C it should be in the range of 6,7 ... 7,7 Ohm.
• If the resistance is lower, it means that there is a short circuit; if more, it means an open circuit. Whatever the case, the valves are not repaired, but replaced with new ones.

Resistance measurement can be made without dismantling, however, the mechanical component of the valve must also be checked. For this you will need:

• From a 12 Volt power source (car battery), apply voltage with additional wiring to the valve electrical connector.
• If the valve is serviceable and clean, then its piston will move down. If the voltage is removed, the rod should return to its original position.
• next you need to check the gap in the extreme extended positions. It should be no more than 0,8 mm (you can use a metal probe to check valve clearances). If it is less, then the valve must be cleaned according to the algorithm described above. After cleaning, an electrical and mechanical check should be made, and then a decision should be made to replace it. repeat.

in order to "prolong the life" of the phase regulator and its solenoid valve, it is recommended to change the oil and oil filters more often. Especially if the machine is operated in difficult conditions.

Phase regulator error

In the event that error DF2 has formed in the control unit on Renault Megan 080 (a chain for changing the characteristics of the camshaft, an open circuit), then you must first check the valve according to the above algorithm. If it works fine, then in this case you need to “ring” along the wire circuit from the valve chip to the electronic control unit.

Most often, problems appear in two places. The first is in the wiring harness that goes from the ICE itself to the ICE control unit. The second is in the connector itself. If the wiring is intact, then look at the connector. Over time, the pins on them are unclenched. in order to tighten them, you need to do the following:

• remove the plastic holder from the connector (pull up);
• after that, access to internal contacts will appear;
• similarly, it is necessary to dismantle the rear part of the holder body;
• after that, alternately get one and the second signal wire through the back (it is better to act in turn, in order not to confuse the pinout);
• on the vacated terminal, you need to tighten the terminals with the help of some sharp object;
• put everything back in its original position.

Disabling the phase regulator

Many motorists are concerned about the question - is it possible to drive with a faulty phase regulator? The answer is yes, you can, but you need to understand the consequences. If, for some reason, you still decide to turn off the phase regulator, then you can do it like this (considered on the same Renault Megan 2):

• disconnect the plug from the connector of the oil supply valve to the phase regulator;
• as a result, error DF080 will occur, and possibly additional ones in the presence of concomitant breakdowns;
• in order to get rid of the error and “deceive” the control unit, you need to insert an electrical resistor with a resistance of about 7 ohms between the two terminals on the plug (as mentioned above - 6,7 ... 7,7 ohms for the warm season);
• reset the error that occurred in the control unit programmatically or by disconnecting the negative battery terminal for a few seconds;
• securely fasten the removed plug in the engine compartment so that it does not melt and interfere with other parts.

Please note that when the phase regulator is turned off, the ICE power drops by approximately 15% and gasoline consumption increases slightly.

Hack and predictor Aviator

Automakers recommend changing the phase regulators every 100 ... 200 thousand kilometers. If he knocked earlier - first of all you need to check his valve, as it is easier. It is up to the car owner to decide whether or not to turn off the "fazik" because this leads to negative consequences. Dismantling and replacing the phase regulator itself is a laborious task for all modern machines. Therefore, you can only perform such a procedure if you have work experience and the appropriate tools. But it is better to seek help from a car service.