What are the symptoms of a faulty exhaust valve in a car?

1 Answers
TuckerFitz
07/30/25 8:41am
The symptoms of a faulty exhaust valve in a car are: 1. Difficulty starting the engine and weak acceleration; 2. Failing emission tests during annual inspections; 3. Black smoke coming from the vehicle's exhaust pipe; 4. Unstable idle or stalling at idle; 5. Flashing check engine light; 6. Burning of engine oil; 7. Increased fuel consumption. The reasons for a faulty exhaust valve are: 1. Quality issues with the exhaust gas recirculation system itself; 2. Improper maintenance; 3. Poor fuel quality; 4. Aging of the exhaust valve. The function of the exhaust valve is to appropriately reduce fuel consumption, improve engine efficiency, lower exhaust temperature, and decrease the formation of nitrogen oxide compounds and carbon monoxide.
Was this review help?
16
0
Share
More Forum Discussions

What Causes Jerking When Accelerating in a Manual Transmission?

If the jerking sensation when pressing the accelerator is a symptom of vehicle malfunction, it is recommended to promptly visit a 4S shop for inspection and repair. Below are the reasons for jerking when accelerating: 1. Excessive carbon buildup in the throttle body, fuel injectors, or intake ducts. Many malfunctions are caused by carbon deposits, and some vehicles may experience jerking due to carbon buildup. It is advisable to regularly clean carbon deposits. 2. Poor fuel quality leading to incomplete combustion. It is recommended to change the fuel. 3. Faulty spark plugs, ignition coils, etc., causing misfires. In such cases, it is necessary to visit a repair shop for inspection and timely repairs to avoid further safety hazards.
5
4
Share

How many seats can a B1 license drive for a bus?

Vehicle length less than 6 meters. A B1 driver's license allows driving "medium-sized buses" (medium passenger vehicles) and small cars. According to the "Road Traffic Safety Law of the People's Republic of China," in China, passenger vehicles with 8 to 19 seats are classified as medium-sized buses. Small cars refer to vehicles with a total mass of 4.5 tons (inclusive), seating capacity (excluding the driver) of 9 people (exclusive), or a vehicle length of less than 6 meters (exclusive). Below is an introduction to the B1 driver's license: 1. Vehicle types permitted by B1 license: medium-sized buses; 2. Permitted vehicles: medium-sized passenger vehicles (including urban buses with a capacity of 10 to 19 people); 3. Other vehicle types allowed: C1, C2, C3, C4, M.
5
5
Share

How to Deal with Slight Sticking in Electronic Power Steering Wheel?

Electronic power steering wheel sticking is mainly caused by incorrect toe-in value of tires, lack of lubrication in the steering gear, floor mats obstructing the steering column, and poor assembly process of the steering gear. The details are as follows: 1. Incorrect toe-in value of tires. If there is a "squeaking" sound when turning the steering wheel while driving, it indicates that the toe-in value is incorrect, causing the front wheels to be non-parallel and resulting in tire wear and sticking. In this case, the toe-in value should be readjusted or a four-wheel alignment should be performed to ensure the tires are parallel. 2. Lack of lubrication. If there is a noticeable "creaking" sound and sticking when turning the steering wheel while stationary, it indicates that the internal components of the steering gear are scraping against each other. In this case, the steering gear should be disassembled and relubricated to ensure smooth operation of the internal components. 3. Floor mat obstruction. If the floor mats are obstructing the steering column, sticking may also occur when turning the steering wheel. The solution is simply to readjust the position of the floor mats. 4. Assembly process. If the steering wheel has quality issues or there were poor assembly quality control problems when the car left the factory, it should be replaced by the manufacturer, and a claim can be filed if necessary.
1
1
Share

Is the Bora a China-specific model?

The Bora is not a China-specific model. The current generation Bora is actually developed on the same platform as the Lavida. As early as ten years ago, the name 'Bora' was equivalent to today's Sagitar, making it a global model. Relevant details are as follows: 1. China-specific models refer to vehicles developed by multinational automakers specifically for Chinese consumers after understanding their unique needs, sold exclusively in China without equivalent models abroad. 2. They can be broadly categorized into two types: China-specific models developed by joint venture brands or multinational corporations for Chinese consumers, and various L versions of existing mature models that are lengthened, enlarged, or feature upgraded configurations as China-specific variants.
5
1
Share

What is the exact sound of engine piston slap?

The sound of engine piston slap is a crisp and rhythmic metallic knocking noise, and this sound varies with temperature changes. Piston slap is an abnormal phenomenon, and when this issue occurs, it is essential to immediately inspect the cause and then proceed with repairs. The following are the main reasons for piston slap faults: 1. Improper repair or assembly leading to excessive clearance between the piston and cylinder, or severe cylinder wear causing excessive clearance. At low temperatures, the piston clearance is larger, resulting in severe piston slap noise. As the engine temperature rises, the piston expands, reducing the clearance and thereby lessening or eliminating the piston slap noise. 2. Incorrect piston installation direction or piston deformation, which disrupts the normal clearance between the piston and cylinder, causing piston slap noise. 3. Poor lubrication conditions, low oil pressure, or excessively low oil viscosity, leading to inadequate splash lubrication on the cylinder walls. This prevents the formation of a normal lubricating oil film between the piston and cylinder walls, causing direct contact and resulting in piston slap. 4. Bent or twisted connecting rods, or improper assembly of the piston-connecting rod group, causing the piston to tilt excessively in the cylinder beyond the permissible range. This not only worsens sealing and lubrication conditions but also leads to abnormal cylinder wear, resulting in knocking sounds between the piston and cylinder walls. 5. Blocked oil passages, preventing normal pressure lubrication; excessively tight fitting of connecting rod bearings or piston pins, causing the piston to collide with the cylinder walls during movement and produce knocking sounds.
3
5
Share

Is Min K a government license plate?

Min K is a government license plate. Min K is used for provincial-level systems and the Pingtan Comprehensive Experimental Zone. Additional information: 1. Scope of use for "Min K" license plates: Provincial-level and central-level units stationed in Fuzhou (including administrative units, public institutions, and enterprises). 2. "Min K" license plates are managed and issued by the Vehicle Management Office of the Traffic Police Corps of the Fujian Provincial Public Security Department. 3. License plates for various cities in Fujian Province are as follows: Min A - Fuzhou (excluding Pingtan County), Min B - Putian, Min C - Quanzhou, Min D - Xiamen, Min E - Zhangzhou, Min F - Longyan, Min G - Sanming, Min H - Nanping, Min J - Ningde, Min K - Provincial-level systems, Pingtan Comprehensive Experimental Zone.
11
2
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.