This might indicate a blown head gasket. Have your vehicle looked at by a professional or you could have serious engine damage.
yellow reside on oil cap is caused by condensation of water and sludge from inside the engine. all petroleum products have a little water in em. your engine needs a good flushing and then oil and oilfilter changes more often
one sing can says a lot: check in your oil cap, if you find some oil sludge, its a big revelation that you have oil sludge problem in the engine
If the oil cap says 5w20, use 5w20. If the cap just has a yellow symbol, use 5w30.If the oil cap says 5w20, use 5w20. If the cap just has a yellow symbol, use 5w30.
you have a blown head gasket . you have ran the car way to hot , and now you have water mixed in with the oil....
Yellow or "milky" sludge on oil filler cap is caused by short, frequent driving and not allowing engine to reach operating temperature because crankcase vapor, inside engine, isn't being allowed to "boil" off of crankcase and starts to film on engine block. Shutting off engine when it's not at operating temperature will cause it to stick to engine then restarting a cold engine, driving short time will start this all over again. Always allow engine to reach operating temp, it's ok sometimes but not all the time.
There is an oil cap in middle of forward valve cover, has a black cap with yellow markings.
water is mixing with your oil. it might be something as simple as moisture making its way into the oil compartment around the cap, or it could be something much more serious -- like a cracked block. take it to a technician.
You can use plain water to get sludge out of your car radiator. You can use Marvel Mystery oil to remove sludge from the oil pan.
usually that sludge means coolant in the oil.might be a bad head gasket.
If the oil fill cap says 5w20, use 5w20.If it just has the yellow symbol, use 5w30.If the oil fill cap says 5w20, use 5w20.If it just has the yellow symbol, use 5w30.
The reason why there is a thick sludge under your oil cap is because the engine ventilates crankcase pressure up through the valve covers, this includes oil residue that builds up under the oil cap over an extended period of time. It is good to have your lubrication system flushed out once a year to prevent this oil sludge build up, and also ensure that the vehicle upkeep is maintained such as regular oil changes and air filter changes. Also when you check the oil take the oil fill cap off and wipe it with a rag or cloth from time to time. You should check your oil level at least once a week.AnswerI agree with Mackman-lots of newer vehicles have oil caps with hollowed out centers that allow moisture and sludge to become trapped within, so that the sludge does not continue to circulate throughout the crankcase. It is a very sensible idea to wipe off the inside of the cap periodically. AnswerAlso a bad PCV valve can cause this. The pcv valve allows byproducts and vapors of combusion to be re-introduced back into the engine for re-combustion. The valve is usually located at or near the oil cap. If it malfunctions or gets clogged over time (most of them do eventually) this can cause the vapors to build up in the oil reservoir and associated compartments. PCV valves are cheap (5-10 bucks) and are easy to replace in most cases.
No, there is a yellow cap marked "oil" under the top engine cover.