#Valve check on 250 cg engine code#

The PCV valve function is to eliminate crankcase emissions from the crankcase and send them to the intake. PCV valve stands for Positive Crankcase Ventilation, and it is one of the oldest and most used emission devices in many vehicles. If the PCV valve is faulty and causing a rich or lean mixture to the engine, you can get symptoms like white or black smoke coming out from the exhaust pipe, depending on what type of mixture problem the engine has.Ī short conclusion is: If you see any strange smoke from the exhaust pipe, make sure that the PCV valve is in good shape. This will cause a lot of blue smoke from the exhaust pipe.

If the PCV valve or the hoses are blocked, the crankcase will push up oil into the combustion chambers, which will cause oil to burn inside the engine and go out through the exhaust pipe. If you suddenly see several large oil leaks and increased oil consumption in your car, check the PCV valve and the hoses to it to make sure they’re not blocked. If the PCV valve or the hoses are blocked by moisture, you will get a very high pressure inside the engine crankcase, which will push the pressure up in the cylinders and out from the gaskets. On most cars, you won’t feel a broken PCV valve on higher RPMs than idle, but it’s worth mentioning because it can happen depending on the valve’s design. When you have a faulty PCV valve, causing a wrong fuel mixture, you can feel that your car has rough acceleration on high and low RPMs. If you have a mixture that is too rich, you can turn off the spark with the fuel and therefore cause a misfire. If you have a too lean mixture, the cylinders won’t fire up correctly, which can cause misfires. Misfiresīecause you can get a faulty lean/rich mixture due to a faulty PCV valve, you can feel misfires on both idle or acceleration when your PCV valve is bad. Lean mixture is more difficult to find, but it often causes misfires, as we will discuss next. Rich mixture, you can often see that the car has a little more gray/white smoke than usual, and you can often feel a smell of petrol. Usually, your air/fuel mixture will become lean, and you can feel the same symptoms as from a lean mixture. Lean/Rich Mixtureīecause of the issues discussed, a faulty PCV valve can have the same symptoms as an intake leak, and the air/fuel mixture can end up being wrong. If you have any strange idle problems, it’s always a good idea to check the PCV valve first. High Idle RPM/Rough Idleīecause the PCV valve controls the airflow between the crankcase and the intake manifold, a broken PCV valve can have the same symptoms as an intake air leak, which can cause the idle RPM to get too high and other strange idle behaviors like very rough idle. Some older cars with a PCV valve fitted without an electronically controlled engine will not have this symptom.

#Valve check on 250 cg engine code#

To read the trouble code from the engine control unit, you have to use an OBD2 scanner. When the engine light shows up, there is a trouble code stored in the engine control module. The most common and most noticeable sign of all bad PCV valve symptoms is probably a check engine light on your dashboard. Here is a more detailed list of the signs you should look for: Check Engine Light White/Black/Blue Smoke from the ExhaustĪs you can see, most of the symptoms are engine performance problems, which could also be caused by other issues, so it’s important to research the subject carefully.The main symptoms of a bad or failing PCV valve include: