But having changed their car to a more modern one, many car enthusiasts continue to turn to the same mechanics. And they lack the courage to admit that they do not understand the complex processes in fuel systems and electronic ignition circuits. They look for a spark to break through, breaking through transistors, the insulation of the coil windings, high-voltage wires, and "breaking" conductive paths on the covers and distributor runners. Without solving the problem, such mechanics drive the "disease" inside. And in the end, the owner still goes to professionally trained engineers. But "treating" the machine is already significantly more difficult.
Specialists often find themselves in a situation where, after a long period of work, even with the help of instruments, they cannot understand anything. And only after some time it turns out that the previous "smart guy" tweaked the jets in the carburetor or tweaked everything in the injector, and in the end broke its tightness or burned out the pressure sensor.
The list of possible reasons leading to increased fuel consumption and decreased power is quite extensive. And besides these, there are a number of uncharacteristic but frequently occurring malfunctions, such as piston burnout, fuel getting into the oil, failure of one of the injection system temperature sensors, failure of the thermostat, mixing up of vacuum tubes, destruction of one of the carburetor gaskets, piston rings or piston partitions.
Diagnostics must be carried out without disassembling, since otherwise there is a high chance of only temporarily eliminating the consequence or even adding new, sometimes more complex, problems to the existing one.
For example, there are many reasons that lead to a decrease in spark power. If diagnostics are performed on a multifunctional motor tester, the defect can be immediately determined on its screen. It is impossible to evaluate in any other way the correspondence of the form of the spark formation process to that in which complete combustion of fuel occurs in various operating modes.
It is a common situation when, having discovered signs of abnormal operation in the engine, a car enthusiast goes to a mechanic. Having measured the engine compression and found it to be within the norm, he begins to adjust both the carburetor and the ignition system, achieving stable operation. Sometimes it works. The engine starts properly and stops stalling, but the traction and fuel consumption leave much to be desired. What is the mistake?
In a worn engine, leaks in the valve seals often appear. Oil leaking onto the pistons results in artificial compensation of the gaps that arise due to wear of the pistons, rings and cylinders. And when measuring compression, false readings are obtained. Fixing this problem after a "repair" performed by a mechanic is significantly more difficult due to the need to restore the original settings.
The opposite situation is also quite common, when the owner is unjustifiably "pushed" into a major overhaul, although it would be enough to replace the same seals, which are more than 10 times cheaper.
Unfortunately, the car maintenance market still has a roughly equal division between stations that meet modern requirements for qualifications, technical and cultural maintenance, and the fragments of the sadly memorable Soviet car service. Therefore, car owners should carefully examine the technical center in whose pit they park their car. And not so much with the cost of services, but with how, with what and under what conditions the car will be diagnosed and repaired.