The era has gone when we wrote about the secrets of the carburetor from room to room. It helped someone to realize that this device does not present insurmountable tasks - they are “with you” with it. Others hoped for the coming technical revolution - injection would come to Russia … and save you from problems. The machine will become completely low-maintenance and environmentally friendly.
But remember: "it was smooth on paper …". The injection in Russian has brought many new troubles, and an important detail distinguishes them from the previous ones: you have to shell out for someone’s hack more and more often and spend considerable money. As a rule, it is not possible to eliminate defects in the old fashioned way - “cleared, blew, rode”. At the same time, it is impossible to save money by delaying repairs: gasoline is becoming more expensive and its overspending hurts the budget.
Here, for example, is a fuel mass flow sensor. Very expensive, but by no means as reliable. Recently, one client was indignant: the DMRV did not pass even 30 thousand km, and his signal during testing reached 1.157 V (a working sensor with the ignition on should give 0.996 V). As experience has shown, a signal of 1.016 V is the upper limit of a reasonable allowance, and a signal of 1.035 V indicates glaring malfunctions! Meanwhile, many car owners, especially from the hinterland, are trying to save money by delaying the replacement of the DMRV. They came to us with a signal of 1, 055 V - this is when the engine is already twitching, "troit", whipping excess fuel, and what can we say about toxicity …
Here the oxygen sensor will not save either - the unstable DMRV signal is confusing to any lambda probe. It would be interesting to hear the arguments of the proponents of such a "saving."
Another problem of injection machines is air leaks in all possible places after the air intake manifold. Everyone understands: air not taken into account by the system depletes the mixture entering the cylinders, and the electronic unit does not know about it - and here you have problems. The "left" air sometimes finds amazing loopholes. Has rolled to us "ten" with unstable idling. They didn’t succeed in setting the required toxicity: the mixture was depleted, the CO content was lower than 0.4%, but the HF was over the top. We got even to the "brain" of the computer - raised, as much as possible, the correction coefficient … all to no avail. Strange as it may seem, experience has failed us: the least expected was a trick from the idle controller, and it was he who was to blame. Excess air penetrated between the body and the plastic part. Kerosene spilling easily confirmed this, and the liquid that temporarily tightened the gap immediately allowed to regulate toxicity. Threw this IAC - with the other, the engine worked fine.
And here is an example of a curious relationship between the mechanical state of an engine converted to gas and its injectors. It was possible to eliminate a complex malfunction when one of the valves of the 2111 engine was deeply seated in the saddle, which ended in a drop in compression by half. It is clear that the car came to us in a state of almost feverish shaking, with terrible toxicity, etc.
Having wised up with a valve, a saddle and a pusher (technology is beyond the scope of today's topic), the compression in the cylinder was restored. But even after that, the gas engine did not work well, although it was just fine on gas. What would you do? Of course, we checked the nozzle! And not in vain: of the four holes, three were coked. Apparently, the owner did not pay attention to the problems for a long time, and missing flashes in the cylinder affected the nozzle - soot, tar did their job.