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Causes and Solutions for White Smoke from the Dipstick

Model: (Various brands) Various
Part: Checks and maintenance

In this video, we see what it means if white smoke comes from the oil dipstick or the filler neck and PCV valve, resulting in power loss and low compression in the cylinders. The reason is excessive pressure in the crankcase: combustion gases pass from the pistons to the crankcase. Tests can be performed to rule out blockages: if smoke comes out when opening the oil dipstick, it means there are oil vapours due to high pressure. If smoke also comes out when opening the oil cap, then there is no blockage between the crankcase and cylinder head. If smoke comes out when disconnecting the PCV valve, the valve is not blocked. The conclusion of these tests is that there is wear in the piston rings: the segments no longer seal, allowing gases to enter the crankcase. You must replace the pistons and segments. The smoke comes because the worn rings can no longer contain the combustion gases, which end up in the crankcase, increasing the pressure, and the white smoke is burnt oil mixed with exhaust gases.

Posted on 4 March 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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