Note. If the original spark plugs are re-installed on the engine after checking the condition, they must be screwed strictly into the previous cylinders - make the appropriate marking.
All car models covered in this manual are equipped with transverse engines. Spark plugs are installed on top of the engine.
Tools needed when changing spark plugs
1. Candle head — Equipped with a special soft insert, which excludes the possibility of accidental damage to the porcelain insulator when the candle is turned inside out. 2. Torque wrench — Although not mandatory, it provides a reliable guarantee of the correct tightening torque of the spark plugs. 3. Ratchet drive - It is used in a set with a candle head and a torque wrench. 4. Extension - Depending on the model and its accessories, access to the spark plugs may be limited to varying degrees, so the use of extension cords of the appropriate shape and design will greatly facilitate the procedure. 5. Tool for measuring and correcting spark plug gaps - Several types of this kind of tools are available - make sure that the tool is equipped with a dipstick that matches the size of the gaps of your car's spark plugs. |
In most cases, a special spark plug head is required to replace spark plugs (with soft lining inside) complete with a ratchet drive, as well as a set of wrench drive extensions and a tool for checking and adjusting the interelectrode gaps (see illustration above). A special tool is also available for safely disconnecting the BB wire tips from the spark plug shanks, although its use is not strictly required. Using a torque wrench will allow you to achieve the correct tightening torque for the candles.
It is best to keep a set of replacement spark plugs with a correctly adjusted electrode gap in the car at all times. When buying new spark plugs, make sure that they meet the requirements of your car engine in terms of their parameters. The necessary information is given in Specifications to this Chapter, as well as on the VECI label attached under the hood (in case of discrepancy, preference should be given to the requirements of the latter).
1. Wait for the engine to cool completely, only after that proceed with turning out the candles. In order not to waste time in vain, use the pause to check the status of the replacement set of candles.
2a. The interelectrode gap of the spark plug is checked by inserting the appropriate meter probe into it (see accompanying illustration) and must comply with the requirements given on the VECI label (alternatively see chapter Engine electrical equipment). The probe should slide with slight resistance between the side and central electrodes of the section.
2b. The gap can be adjusted using a special tool, usually included in the meter - bend the side electrode of the spark plug accordingly (see accompanying illustration). If the side electrode is not positioned exactly above the center electrode, correct its position accordingly. Check for cracks or other damage in the porcelain insulator of the spark plug. The presence of any kind of defects in the insulator is unacceptable.
3. On Integra models, remove the spark plug cap (see accompanying illustration). With a cold engine, disconnect the BB wire from the spark plug of the first cylinder (see Checking the condition and replacing the explosive spark plug wires, cover and distributor slider (every 48,000 km or every 24 months)). Pull only on the tip, and in no case on the wire! It would be wise to use a special tool.
4. If you have a source of compressed air at hand, use it to remove debris from the spark plug niches of the engine (For this purpose, a conventional bicycle pump is no worse).
Attention! Remember to wear protective goggles when using compressed air!
5. The spark plugs on the models in question are deeply recessed into the candle niches, so you will need a key drive extension to turn them out. Putting on the candle head, connect the drive and, gently turning the gate counterclockwise, unscrew the candle (see accompanying illustration).
6. Check the removed spark plug against the condition map shown in the photographic insert to give a good idea of the overall condition of the engine. Before screwing in new spark plugs, lightly lubricate their threads with anti-seize sealant (see accompanying illustration).
7. Thread one of the new spark plugs into the appropriate hole in the engine by hand. After making sure that the candle is not skewed in the thread, tighten it with the required force (with a torque wrench handy). To facilitate the procedure for baiting a candle, pull a piece of flexible fuel hose onto its shank (see accompanying illustration). This eliminates the possibility of thread breakage, since at the slightest biting, the hose will simply begin to turn. 8. Follow procedures before connecting BB wires to spark plugs Checking the condition and replacing the explosive spark plug wires, cover and distributor slider (every 48,000 km or every 24 months).
9. Connecting the BB wire is carried out by rotational-translational movements of its tip - the latter should sit tightly on the shank of the candle.
10. Repeat the procedure for the remaining spark plugs, performing all steps in turn to avoid disturbing the order of connecting the BB wires.
11. On Integra models, reinstall the spark plug cap.
Spark Plug Status Map
The normal state of the candle
Symptoms: Gray-brown color and slight wear of the electrodes. The number of glow plugs corresponds to the type of engine and its general condition.
Recommendations: When replacing spark plugs, use spark plugs of the same type.
Wear
Symptoms: Rounding of the electrodes with a slight accumulation of deposits at the working end. The color is normal. Causes engine start difficulty in cold, wet weather and increased fuel consumption.
Recommendations: Replace the spark plugs with new ones of the same type.
Coal deposits
Symptoms: The presence of soot indicates an over-rich air/fuel mixture or a weak spark. Causes misfiring, difficult starting and engine instability.
Recommendations: Check if the air cleaner is clogged, if the fuel level in the float chamber is too high, if the air damper is stuck, and if the contacts are too worn. Try using plugs with a longer insulator, which increases fouling resistance.
Ash formation
Symptoms: Soft brownish deposits on one or both spark plug electrodes. The source of their formation is the additives used in oil and/or fuel. Excessive buildup can insulate the electrodes and cause misfiring and engine instability when accelerating.
Recommendations: If deposits build up quickly, change the oil seals to prevent oil from entering the combustion chambers. Try changing the brand of fuel.
Oiling
Symptoms: Lubrication of the spark plug is caused by wear on the valve stem seals. Oil enters the combustion chamber through worn valve guides or piston rings. Causes misfiring, difficult starting and engine instability.
Recommendations: Carry out mechanical restoration work and replace the spark plugs.
Closing the electrodes
Symptoms: Waste products of combustion enter the interelectrode space. Solid deposits accumulate, forming a jumper between the electrodes. Leads to ignition failure in the cylinder.
Recommendations: Remove deposits from the interelectrode space.
Overheat
Symptoms: Porous, white insulator, electrode erosion and absence of any deposits. This will shorten the life of the spark plug.
Recommendations: Check if it meets the requirements Specifications number of glow plugs installed, ignition timing correct, air/fuel mixture too lean, intake manifold vacuum leaks, and stuck valves. Also check the coolant level and check if the radiator is clogged.
Too early ignition
Symptoms: The electrodes are melted. The insulator is white, but may be dirty due to misfiring or foreign particles entering the combustion chambers. May lead to engine failure.
Recommendations: Check the glow number of the installed candles, the ignition timing, the quality of the mixture (isn't it too poor), whether the cooling system is clogged and the lubrication system is functioning properly.
Electrically conductive gloss
Symptoms: The insulator has a yellowish color and a polished appearance. It speaks of a sudden increase in temperature in the combustion chambers during sharp acceleration. At the same time, ordinary deposits are melted, acquiring the appearance of a varnish coating. Causes misfiring at high speeds.
Recommendations: Change spark plugs (colder, while maintaining driving style).
Detonation
Symptoms: Insulators may be chipped or cracked. Insulator damage can also result from inaccurate spark plug gap adjustment. May damage pistons.
Mechanical damage
Symptoms: May be caused by foreign material entering the combustion chamber or by the piston hitting a spark plug that is too long. Lead to cylinder failure and piston damage.
Recommendations: Remove foreign particles from the engine and/or replace. Since the service life of the candles is usually 15,000 km, it is sufficient to clean them every 8,000 km.