How is motor oil classified into grades?

What Causes Transmission Abnormal Noise?

Transmission gear abnormal noise is usually caused by low or deteriorated transmission oil level, excessive or insufficient gear meshing clearance, or poor gear engagement. When diagnosing the cause of transmission abnormal noise, the pattern of the noise should first be identified, and then possible fault causes and solutions can be further determined based on the situation. Below is relevant information about the transmission: 1. When the transmission meshing clearance is too large, the driving gear impacts the driven gear during rotation, producing a knocking sound. This noise usually worsens as the transmission temperature increases. When the meshing clearance is too small, the abnormal noise is usually continuous, sometimes uniform and sometimes uneven. The faster the vehicle speed, the more severe the noise, and it often causes the transmission lubricating oil to overheat. Gear noise can also be caused by damage to the gear tooth surface. This noise is uneven, rhythmic, and increases with greater throttle input. In severe cases, vibration of the transmission can be felt. 2. If abnormal noise from the transmission area is heard in the cabin during idle or driving, possible causes include: insufficient transmission oil or deteriorated oil quality; worn, loose, or damaged transmission bearings; bent transmission shaft; abnormal gear engagement with excessive or insufficient meshing clearance; metal spalling on gear tooth surfaces, broken teeth, or misalignment during repair or assembly; loose connection between the gearshift lever and the shift fork groove. Corresponding measures: If there is a metal dry friction sound during driving and the transmission housing feels hot to the touch, this is caused by insufficient or deteriorated lubricating oil. Oil should be added or the oil quality checked, and replaced if necessary. 3. If there is abnormal noise in neutral, which disappears when the clutch pedal is depressed, it is usually due to wear or looseness of the front and rear bearings of the transmission input shaft or noise from the constant mesh gear. If noise occurs in all gears, it is mostly due to noise from the rear bearing of the output shaft. Severely loose or damaged bearings should be repaired or replaced.

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What Causes Unstable Engine Idle?

Here are the reasons for unstable engine idle: 1. Intake manifold leakage: When unauthorized air, fuel vapor, or exhaust gases enter the intake manifold, it causes the air-fuel mixture to become too rich or too lean, leading to unstable engine idle. A simple method for car owners to check for intake manifold leaks: Open the engine hood, remove the air filter from the throttle body. Start the engine and block the throttle with your hand (if the engine stalls, there is no leakage; if it continues running, there is a leak somewhere). If it doesn't stall, don't rush to turn it off. Check nearby pipes for any suction, which indicates a leak. 2. Excessive carbon buildup in the throttle body: Too much carbon deposits in the throttle body and surrounding intake passages change the cross-sectional area of the air channel, making it difficult for the control unit to precisely regulate idle air intake. This also leads to an overly rich or lean mixture, causing unstable idle. 3. Faulty intake system components: There are many actuators in the engine's intake system. 4. Fuel system issues: Problems such as clogged injectors, blocked fuel filters, obstructed fuel pump screens, faulty fuel pressure regulators, or clogged return lines can all result in incorrect fuel injection, leading to improper air-fuel mixture and unstable idle. 5. Ignition system failures: Issues like faulty ignition modules, incorrect spark plug gaps, eroded or damaged spark plug electrodes, or excessive resistance in high-voltage wires can reduce spark energy or cause misfires, resulting in erratic idle speed fluctuations. If your car experiences unstable idle with fluctuating RPMs, it should be addressed promptly. Remember, when this occurs, the engine is no longer operating at its ideal idle speed, leading to worsened fuel economy and reduced environmental performance.

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Why is the ABS light on the car dashboard illuminated?

When the car displays ABS, it indicates a malfunction in the vehicle's Anti-lock Braking System. During emergency braking, if the wheels lock up, the vehicle may lose control and skid, preventing the driver from slowing down or adjusting the vehicle's trajectory, which poses significant safety risks. There are various states in which the ABS light may illuminate, each with different causes and solutions, as detailed below: State 1: ABS warning light remains constantly on (most common). Cause 1: The ABS wheel speed sensor's sensing area is covered by dirt, mud, or other contaminants, affecting its ability to detect the corresponding speed signal. This prevents the ABS computer from determining the vehicle speed and the wheel's slip rate, thus failing to issue appropriate commands to adjust braking. Solution: Clean the dirt from the wheel speed sensor and adjust the gap between the sensor and the signal ring to restore normal function. Cause 2: Loose connections between system wiring or poor contact in the ABS relay result in poor signal transmission, leading to system failure. Solution: Inspect the wiring connections and reconnect any loose parts. State 2: ABS warning light intermittently illuminates but turns off during acceleration. Cause: When multiple vehicle electrical devices are in use, the battery voltage drops below 10.5V. As the engine speed increases, the voltage rises, causing the ABS light to turn off. This may also occur due to insufficient power supply voltage to the ABS system, such as poor terminal contact or grounding issues. Solution: Check the battery's specific gravity; inspect the charging system; examine the power supply (e.g., voltage relay or poor power contact). State 3: ABS warning light remains on after engine start and only turns off when the engine is turned off (IGFF). Cause: Poor grounding contact in the ABS hydraulic valve body; poor electrical connector contact in the ABS hydraulic valve body; ABS computer malfunction. Solution: Loosen and then retighten the grounding screw on the hydraulic valve body, cleaning the contact surface if necessary; check if the connector gap has widened; replace the ABS or ABS/ASR computer. State 4: ABS warning light illuminates during high-speed driving. Cause: At high speeds, the ABS computer detects a significant discrepancy between the rear and front wheel speed signals; incorrect tire or wheel rim specifications. Solution: Refer to the vehicle's tire and wheel rim specifications, as indicated on the label near the fuel tank cap. State 5: ABS warning light intermittently illuminates. Cause: Improper adjustment of the brake light switch; poor internal contact in the brake light. Solution: Start the engine, depress the brake pedal, push the brake switch linkage down fully with your finger, then release the brake pedal to complete the self-setting position; replace the brake light switch if necessary.

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Is the engine of the 2021 Highlander imported?

2021 Highlander's engine is an imported engine. Below is relevant information about the engine: Concept: An engine (Engine) is a machine capable of converting other forms of energy into mechanical energy, including internal combustion engines (reciprocating piston engines), external combustion engines (Stirling engines, steam engines, etc.), jet engines, electric motors, etc. For example, internal combustion engines typically convert chemical energy into mechanical energy. Classification: Internal combustion engines, external combustion engines, meaning the fuel burns outside the engine, gas turbines, jet engines.

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Does Oil Film Remover Damage Glass?

Oil film cleaners do not damage glass. Here are the relevant tips: 1. Cleaning Technique 1: Use clean water to wash away dust on the windshield, then apply the cleaner evenly on the glass with a sponge or soft towel, removing the oil film in a circular motion. The wiper blades should also be cleaned; 2. Cleaning Technique 2: Rinse the cleaner off with clean water and dry the windshield. Regular maintenance cleaning is necessary, but excessive cleaning can also harm the windshield and wipers; 3. Cleaning Technique 3: Toothpaste can also remove oil film. Toothpaste contains fine abrasive particles that, when applied to the glass and wiped, can polish away the tiny holes on the glass, thereby removing the oil film.

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Is the front skid plate of the Senova X35 silver?

The front skid plate of the Senova X35 is silver. Relevant details are as follows: 1. Interior: The Senova X35 features a color-contrast interior design with brown/black combinations that exude a sense of luxury. Additionally, the floating central control color screen and Mercedes-style air vent designs highlight a youthful vibe. 2. Powertrain: The Senova X35 is equipped with the same 1.5L naturally aspirated engine as the X25, delivering a maximum power of 85kW (116PS) and a peak torque of 148Nm, paired with either a 5-speed manual or 4-speed automatic transmission.

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How is motor oil classified into grades?

What Causes Transmission Abnormal Noise?

What Causes Unstable Engine Idle?

Why is the ABS light on the car dashboard illuminated?

Is the engine of the 2021 Highlander imported?

Does Oil Film Remover Damage Glass?

Is the front skid plate of the Senova X35 silver?

What to Do When the Car Won't Start Due to No Power?

How to Fix a Cigarette Lighter That Won't Pop Out When Pressed?

What to Do If the Dash Cam Keeps Falling Off the Windshield?

How often should the automatic transmission fluid be replaced in a 2017 Passat?