10.04.2014

Let me be surprised by some of the messages on the Legion-Avtodata forum in the topic “Conference for auto diagnosticians December 3-6 in Moscow”,

And I, for example, will always be grateful to the training courses from Sergei Pavlovich Gazetin. And I will always remember his words: “first of all, if we suspect a “mechanics” problem, we connect the vacuum sensor and look. If the vacuum is abnormal, we are looking for mechanical problems...a vacuum sensor is like a thermometer for a doctor" No, that's great!

And when this Lancer came in for repairs with the problem of “stalls and won’t move,” what I did right away:
· Do you remember if there was a similar problem on the same car? Was.
· Is everything ready to check the vacuum level? Everything is ready.
· Do you have time to “think”? Eat.
Well, shall we begin?

A similar malfunction: “stumbles and doesn’t move” can occur for a variety of reasons. If you don't have experience in your head similar repairs and don’t know some of the basics, then it’s better not to take on such repairs - you’ll be scattered around and won’t do anything...

Mechanics, the fuel system, and the ignition system may be involved here. And even a “half-wedge” wheel bearing (as an incredible option). And so on. When troubleshooting, it is important to correctly and accurately identify the “weak link” and not be distracted by the unlikely.

It’s not for nothing that the manufacturer writes in its manuals that “before carrying out measurements and checks on a car, you need to prepare it.” Was anyone surprised by this fact? They say, what is there to cook, go ahead, check it out! But in vain, because it follows:

· Check that the coolant temperature is within 80-95°C. If there is no such temperature, you need to start the engine and bring the temperature up to the set temperature. Does anyone not do this? Well, don’t do it (“to each his own”?), then you will wonder why the data taken is “something different.” Everything is correct here, the manufacturer will not recommend anything unnecessary!
· Turn off all consumers: stove, headlights, sidelights, radio, etc. - nothing should be powered by the battery and affect the parameters of the information being recorded.
· Put the gearbox in neutral position; if the gearbox is automatic, put the selector in “P” (parking) mode.
· Turn off the ignition, that is, turn the ignition key to the “OFF” position.

Since I use a dealer MUT3 scanner, I do everything else - again, according to the Manufacturer’s recommendation, the following:

· Disconnect the hose from the positive crankcase ventilation valve and attach a vacuum gauge
· I close the hole in the forced ventilation valve
· I start the engine, check the idle speed - it should be within the required limits

I will focus on point number two: “I close the hole in the forced ventilation valve”; Quite often I get calls from colleagues who have read my articles and want to consult on something, and there were several questions that were answered after I asked again: “Was the hole in the PVC valve closed before the inspection?”

Well, there’s nothing wrong with that, everyone starts somewhere... below is a screenshot from a scanner, look and analyze?

What you can read on the scanner monitor and what we are currently working on:

Incorrect vacuum readings (43 kPa)
· Long Trim and Short Trim parameters have gone negative

Incorrect vacuum readings (43 kPa)
Let's start with rarefaction, although this is not a completely accurate definition. It is more accurate to say “differential pressure”, since we are comparing “barometric” (atmospheric) pressure” and “real (actual) pressure during intake manifold" We call the difference between them “rarefaction”. In our case, differential pressure = 43 kPa. This alone begins to raise questions, since for such motors the value of DP (differential pressure) should be plus or minus 27-30 Kpa. The difference is noticeable and there must be reasons for this.

The Long Trim and Short Trim parameters have gone negative
When these parameters go beyond regulation (average value about 0%) towards enrichment or leanness fuel-air mixture, this may indicate some kind of malfunction in fuel system, in the intake-exhaust system, in the ignition system, etc. You can watch my short video on the topic of the issue - “Before replacement”

Now is the time to use a pressure sensor and really look at the processes taking place:

The red square on the oscillogram highlighted the high-voltage pulse(I’ll call it colloquially: “spark moment”). There, in the red square, there is a number “0”, this is top dead center. It turns out that the “spark ignites” after passing the dead center. So, is it time to look at the gas distribution system? Elegantly open and remove the casing...

For clarity, I drew a white stripe on the timing belt: “Where the mark is located.” The white dot to the right and below is “as it should be.” In the lower right corner of the photo is a screenshot from the manual for this motor.

The alignment mark has shifted and moved back. For what reason? Miracles don’t happen, everything has a reason, and to do this you need to go down the belt and inspect the shaft:

There is unusualness, there is “something” - but only an attentive eye will notice it. Let's look and study the question further:

Did you notice too? There is some wear on the surface. What does this mean, what do you think?

Well, while you’re thinking, you can watch another short video, where everything becomes very clear. Simply indescribable beauty. And you can estimate how far the gear moves to the left and right and how this can affect the operation of the gas distribution mechanism:

Conclusion after the measurements taken: “replace the gear”. After replacing the gear, the differential pressure readings leveled out and became satisfactory for stable engine operation:

And here is my third video - “After replacement”:

But you also need to pay attention to the crankshaft. It’s clear that “the iron there is thick – it won’t wear off!”, but this little thing is still somehow annoying...

Let me briefly summarize the work done and draw my personal conclusions:

How wonderful this renovation looks on paper! And not only this one - all the articles on “repair practice” are “easy, simple, beautiful.” And if you think about it, ask the question: “Where does everything come from?” I think so: - If a person comes to work in a car service, in diagnostics, then he must immediately discard the desire to “Earn a lot! Now! Instantly! Forget about it for now.

And immerse yourself in your studies. There is so much to know that, as one of my friends correctly said: “Damn, there are too few hours in the day!”

That’s why at the very beginning of my story I mentioned studying with S.P. Gazetin - this is a good way to expand the hour frame of the day and in a few days learn and study so much material that would have taken months or years to learn on your own. All these “courses, conferences and similar events” are nothing more than a “squeeze”, like a concentrated thought that the lecturer gives to the audience.

P.S While I was writing this article (and I wrote it for a long time, you understand - there is little time), the Legion-Avtodata company announced aSecond conference "Car repair technologies. Diagnostics of modern power units" at the end of March 2014,- .

It matched well. I looked at the conference program - it was interesting. Designed for a wide range of automotive specialists. But since I deal mainly with gasoline Mitsubishi cars, Toyota, then I chose for myself the lecture by S.P. Gazetin:"Diagnostics gasoline engines based on oxygen sensor signals and lambda circuit parameters using a scanner and oscilloscope."

From a practical point of view, the following topics are very interesting to me:
8. Fuel correction and fuel adaptation, parameters describing the processes of fuel correction and adaptation, their interpretation (adaptive corrections, additive and multiplicative correction, possible options displayed on the scanner display).
9. Use of fuel correction and adaptation parameters for diagnosing the engine and its systems. Book Mitsubishi Lancer 9 2003-2007 right-hand drive petrol models, spare parts catalogue. Car repair and operation manual. Legion-Avtodata

Hello dear users of the site site. A story happened to me here. After replacing the battery idle speed started to drop on my Lancer 9 (or rather, not after replacement, but after my Lancer stood without a battery for about a day).

At the same time, the revolutions dropped so much that when starting the car I had to press the gas pedal to prevent the car from stalling. Those. Lancer stalled immediately after the factory. I had to read a lot, a lot of information on the Internet, and now I’m sharing it with you.

According to information on the Internet, there may be two reasons why the revs are reduced and the car sometimes even starts to stall.

Reason 1 (and the easiest to solve). That's what Lancer has reduced speed The “brains” of the car are to blame. They need to be retrained, or rather, idle training must be carried out.

I found three ways on the Internet idle training Lancer 9. I’ll say right away that the third method helped me, the other two were not successful, and the speed was still reduced.

Method 1. This method is taken from the Lancer manual. As I already said, it didn’t help me, but you should definitely try it (picture is clickable):

Method 2. Found it on the Internet:

1. We warm up the car until operating temperature
2. Reset the terminal for about a minute.
3. We put the terminal back on.
4. Turn off all consumers (turn off the air conditioner, heater, headlights, radio) and start the car for 10 minutes (without load)
5. Turn off the ignition and start it again, but turn on the load to the maximum (heating, air conditioning, high beam etc.) for 10 minutes.
6. We turn off the car - the training is completed.

Method 3. I was already desperate to get the idle speed in order, fortunately I came across this method, it helped me:

1. We remove the terminal from the battery for 10-15 minutes (the positive or negative terminal does not matter).
2. We put the terminal back on (after 10-15 minutes).
3. We start the car and let it run for exactly 10 minutes. idling, ALWAYS all loads are turned off (i.e., lights, stove, air conditioner, radio, etc. are turned off). My rpm in this mode was about 2000.
4. We turn off the car, pause for 10 seconds, start it again.
5. We wait for the engine to warm up to operating temperature and look at the speed - if it reaches 750-800, then great. After that, I went on business and my speed no longer dropped.
6. In the next 100-150 kilometers, everything should return to normal.

Reason 2 (more complicated, and sometimes more expensive). In this case, removing the battery only coincided with the main cause of the fall idle speed. The culprit is the idle air control (IAC), and it can simply become damaged (and need to be replaced), or you just need to clean it. I will try to tell you in more detail about what I found about the IAC on our Lancer 9, and about the methods of servicing it, in the next article.

So located in engine compartment components whose malfunction affects the dynamics of the car.

There are many reasons for the deterioration of dynamics, the main ones can be defined as follows.

1. Engine malfunction - decreased compression in one or more cylinders, leakage of additional air into the engine intake tract. Coking of the exhaust system or damage to the exhaust gas catalysts.

2. Malfunction of the power supply system - clogged injectors, fuel filter and fuel supply system hoses. Insufficient fuel pump supply. Use of low-quality fuel.

3. Malfunction of the ignition system - failure of the spark plug, breakdown of the high-voltage circuit of the system.

4. Malfunction of the engine management system - failure of the system sensors. If any sensor fails electronic unit control switches to working according to a backup program, allowing you to get to a garage or car service center, but at the same time the power and economic characteristics of the engine are reduced.

5. Slipping of the clutch of a car with a manual transmission due to wear or misadjustment.

6. Slippage of automatic transmission clutches due to insufficient quantity working fluid or hydraulic system malfunction.

7. Malfunction brake system- braking of one or more wheels while moving, incorrect adjustment parking brake.

8. Insufficient air pressure in tires.

9. Vehicle overload.

Full diagnostics of the car should be carried out by highly qualified technicians using special diagnostic equipment, so contact a car service center.

You can do the following work yourself.

1. Check and adjust tire pressure to normal.

2. Check the operation of the service brake system and parking brake. It is not necessary to remove the wheels for this. Find a flat section of the road and, in dry, windless weather, conduct a test run to determine the vehicle's run-out. The car must be fully fueled, with only the driver in the cabin. Accelerate the car to 50 km/h, you-

equalize the speed, and then turn off the gear and coast until it comes to a complete stop. Make another run in the opposite direction. The run-out should be about 500 m.

3. Check the operation of the ignition system as described above.

4. Check the operation of the clutch of a car with a manual transmission. The initial check is carried out on a level area free of obstacles. Use the accelerator pedal to increase the speed crankshaft in idling mode - approximately 1500 min" 1. Brake the car with the parking brake. Depress the clutch and engage 1st gear. Then begin to smoothly release the clutch pedal. If the engine stalls, the clutch is working properly and does not slip. If the engine does not stall, the clutch is worn out and requires replacement or drive adjustments.

NOTE

You will find a method for adjusting the clutch drive of a car with a manual transmission in section. 4" Maintenance"(see "Adjusting the clutch release drive", p. 66).

5. Check the functionality of the automatic transmission clutches and the torque converter freewheel when the torque converter is locked.

NOTE

Before checking, the oil in the gearbox must be warmed up to a temperature of 70-80 ° C during a short trip. The temperature of the liquid in the engine cooling system should be 80~90 "C.

When checking the locking torque of the torque converter, the maximum engine speed is determined at full load and in the “D” and “R” positions of the selector lever. At the same time, the functionality of the torque converter stator freewheel clutch and the holding capacity of the gearbox clutches, as well as the downshift brakes and reverse.

Perform the check in the following order:

Check the level of working fluid in the gearbox housing (see “Checking the level and adding oil to a manual transmission and working fluid to an automatic transmission”, page 51);

Place chocks (chocks) under the rear wheels;

WARNING

There should be no people in front or behind the vehicle during the inspection.

Connect the control tachometer;

NOTE

For preliminary check in garage conditions With a sufficient degree of accuracy, you can use the tachometer installed in the car’s instrument cluster.

Raise the parking brake lever all the way and press the brake pedal all the way;

Start the engine;

Set the selector lever to position “D”, press the accelerator pedal all the way and keep it pressed until the maximum tachometer reading (after this point, the crankshaft speed stops increasing even with the accelerator pedal fully depressed).

WARNING

Keep the accelerator pedal depressed only as long as necessary to obtain the maximum tachometer reading, and never hold the pedal down for more than 5 seconds. If it is necessary to repeat checking the torque converter locking torque, first let the engine idle for 2 minutes (the selector lever must be in the neutral position) to reduce the temperature of the working fluid in the gearbox.

The crankshaft rotation speed at the moment the torque converter is locked should be 2200-2800 min."

Move the selector lever to the “R” position and repeat the torque converter locking torque check as described above.

Possible test results:

The crankshaft rotation speed when the torque converter is locked is higher than normal when the selector lever is in position “D”. If the engine speed at which the torque converter locks up is higher than normal, then the cause may be slippage of the rear clutch or freewheel of the gearbox. In this case you should check hydraulic system to determine the cause of slippage;

The crankshaft rotation speed when the torque converter is locked is higher than normal when the selector lever is in the “R” position. If the engine speed at which the torque converter is blocked is higher than normal, then the reason lies in the slipping of the front clutch or brake of the overdrive and reverse gearbox. In this case, the hydraulic system should be checked to determine the cause of the slippage;

See also: