Hi, I would really appreciate your help on this. I have a 1990 Honda CRX. I just changed my valve cover gasket and now there is smoke coming from the dipstick? Could it be coming from the oil tube? Thank you very much.
Hey Kao, what is happening?
You think the valve cover change started the smoke coming out of the dipstick tube? In most cases smoke comes out the dipstick tube because there is excess backpressure inside the engine – called “blowby”. This can be caused from a restricted PCV system, like a bad PCV valve, or from clogged up drain back holes in the top of the cylinder head not allowing the oil to drain back into the engine fast enough, or from worn out piston rings due to excessive wear on the engine.
However, most 4 and some 6 cylinder Japanese engine will not even run if you take the oil filler cap off, and most will have some slight smoke out the oil filler cap and possibly the oil dipstick tube. So, if you checked the items listed above, and don’t see a problem I don’t think I would worry to much about it unless the smoke is excessive, then you might want to run a compression test on the engine to check for wear.