3.3. Interruptions in operation of the engine

Diagnostics of a condition of the engine on appearance of spark plugs



At interruptions the engine unevenly idles, does not develop sufficient power, is raised spends gasoline. Interruptions, as a rule, are explained by malfunction of nozzles or an electrogasoline pump (for more details see. "Control system of the engine"), malfunction of a spark plug of one of cylinders, an air suction in one of cylinders. It is necessary to find malfunction and whenever possible to eliminate it.
1. Launch the engine and leave it to idle. Approach an exhaust pipe and listen to an exhaust sound. The sound has to be equal, "soft", one tone. Cottons from a pipe through regular periods demonstrate that one cylinder does not work because of failure of a candle, lack of a spark at it, refusal of a nozzle, about a strong suction of air in one cylinder or considerable decrease in a compression in it. Cottons through irregular periods arise because of pollution of sprays of nozzles, strong wear or pollution of spark plugs. If cottons occur through unequal periods, it is possible to try to replace independently all set of candles irrespective of a run and appearance, however it is better to do it after the address on car service for diagnostics and repair of a control system of the engine.
2. If cottons are regular, stop the engine and open a cowl. Check a condition of wires of system of ignition. Isolation of high-voltage wires should not be damaged, and tips of wires should not be oxidized. If damages of wires are found, replace a faulty wire.
3. Remove tips of high-voltage wires and turn out candles a candle key. Attentively examine candles and compare their appearance to the photos provided further. The gap between electrodes of a candle has to be 0,70–0,85 mm. If a candle black and damp, it can be thrown out.
4. If all candles look serviceable, establish them into place and connect high-voltage wires. The operating procedure of cylinders 1-3-4-2, numbering of cylinders (1, 2, 3, 4) is conducted from a pulley of a bent shaft of the engine.
5. Take a spare candle. In any way record it on the engine.

Prevention
Do not fix a candle on an oil-filling mouth, the masloizmeritelny probe, fuel hoses.

The reliable contact of the case or carving part of a candle with "weight" is optional, but is desirable. Connect a high-voltage wire from the 1st cylinder to a spare candle. Launch the engine. If interruptions of the engine amplified, replace a candle in the 1st cylinder obviously serviceable. Put on a high-voltage wire and launch the engine. If interruptions amplified, consistently repeat the procedure of item 5 with all cylinders to reveal a faulty candle.
If as a result of the taken measures interruptions of the engine are not eliminated, address to car service for diagnostics of system of ignition at the stand or for diagnostics of the engine — measurement of a compression. The normal compression — more than 1,1 MPas (11 kgfs/cm2), a difference more than 0,1 MPas (1 kgf/cm2) in one cylinder testifies to need of repair of the engine.
6. For elimination of a suction of air tighten all nuts of fastening of an inlet pipe and a final collector or replace laying. If this measure does not yield result, remove a hose, the connecting vacuum amplifier of brakes with the engine, reliably muffle it and launch the engine.
If interruptions in operation of the engine stopped, diagnostics and replacement of the vacuum amplifier of brakes is required (see section 9 "Brake system").
If interruptions in operation of the engine continue, try to pour over a hose outside liquid of the WD-40 type. If interruptions in operation of the engine at least on a short period stopped, try to replace a hose — perhaps, in it there is a gap.