Audi A4 Oil Filler Caps
The oil filler cap may be one of those things in your Audi that you do not think about, at least for a while. It is true that you can forget to put the cap back on and drive around for a few miles before the check engine light comes on. You can find a selection of Audi A4 oil filler caps to choose from in the case that you need a replacement.
Why are these caps important?The oil filler cap keeps moisture, dirt and debris out of the oil tank. Driving around with a tank half-full of filthy oil will shorten the life of your engine. It also keeps it from splashing out and contaminating the engine bay and the underside of the hood. It is not just that the tank is uncovered, but the cap sits on a valve cover that controls the pressure. Removing it causes the oil to erupt when the engine is turned on. Not only that, it causes a vacuum leak that drags unfiltered air into the tank. Engine oil might even fall onto a place that is exceptionally hot, and start to smoke or ignite. Even if you do not see smoke or fire, driving around without a cap can drain the oil tank quickly.
What should you do if you lack a cap?Put a towel over the hole, avoid driving your car, and buy a new cap right away. The good thing about these caps is that they are universal and can fit many cars, including your Audi. You might even want to buy more than one. You should also change your oil, even if you have recently had it done. This is because your tank has sucked in contaminants while the cap was off.
When should you replace your filler cap?You should replace your filler cap if it leaks, is broken, or when you see a lot of gunk and residue on the bottom side of a cap that does not come off easily. You will also see wasted engine oil around the opening of the oil tank. Another sign that a cap may be leaking is your spark plugs misfiring, because they have been fouled with leaking engine oil.
How do you replace the filler cap on your A4?Open the lid of the old cap, and rotate it until the arrows on the rings line up. Then, pop it out with a flat head screw driver. Spritz some brake cleaner on a rag, and clean around the area to sop up any excess gunk. Then, put the cap on, line up the arrows, and push the cap down and rotate it until you know it is secure. Close the lid and rotate it again until it is firm and airtight in its seat.