How To Diagnose Leaks Under Your Car | Autoblog Wrenched

All too often you back out of your driveway and see drips or puddles underneath your car. Should you worry? We'll teach you how to diagnose them on this episode of Wrenched.

Watch all of our Autoblog Wrenched videos for more tips on how to diagnose, fix, and modify cars from professional detailer Larry Kosilla. While you're at it, check out Larry's other car cleaning and maintenance video series Autoblog Details!

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[00:00:00] All too often you back your car out of a parking spot and see drips or puddles of fluid, but what is it, where is it from and should you worry? Find out on this episode of Wrenched. Here's what you'll need to do the job: catch can or cardboard, oil dry, rags, gloves, flashlight, and your nose. I'm Larry Kosilla, pro detailer and trainer for the last 15 years but it when it comes to what's under the hood, I'm the student. Follow me as experts teach me how to diagnose, fix

[00:00:30] and modify cars on autoblog's Wrenched. While some cars have under trays, most however are open and when a leak occurs, it collects on the ground under or near the faulty part, giving a mechanic a good idea of what part it could be from and where to look. The only problem is, your mechanic isn't usually there when the leak occurs so it's up to you to decide if it's normal, a concern, or a major issue. And keep in mind the original color of the fresh fluid may not be

[00:01:00] the current color of the old leaky fluid. Once the fluid's been in the car for a while they gather contaminants and begin to look the same so it can be confusing. When I first noticed some leaks under my car, what are some potential tips to help me determine whether it's something to panic about or it's normal. - There are up to eight different fluids that potentially could be leaking on the ground. Depending on the fluid, that will really give us a clue as to where the leak is coming from. - [Larry] Clear water dripping from your engine is typically caused from condensation accumulating

[00:01:30] on your AC condenser on a hot day while blasting ice cold air in your car. This of course is normal and this type of sweating will evaporate quickly especially on hot pavement. Washer fluid is typically light blue in color and has little to no scent. This type of drip is common immediately after refilling the washer fluid reservoir as some may have spilled on the floor. If you haven't recently topped off the fluid, check the connections to the reservoir for leaks and that you've tightened down the cap.

[00:02:00] This is harmless and nothing to worry about. If the fluid is pink or reddish it could be power steering fluid or transmission fluid. Both of which need to be addressed quickly. If it smells like burnt oil it may likely be power steering fluid but be sure to use the dipstick to check the level. Having a low register on the stick may further indicate you have a power steering leak. If the leak is further back or towards the center of the car, it might be worth looking over

[00:02:30] the transmission for any obvious leaks as well. Transmission fluid smell is quite subjective. Some say burnt oil, rubbery or even a mildew type smell. Regardless, it's time to visit a mechanic. Now anti-freeze on the other hand is usually a bright color like yellow, green or orange. It has a low viscosity similar to water and has a sweet smell like syrup. This is very toxic and should be cleaned up immediately or put in a catch can or disposable tray under the leak. Check your reservoir to see if it's low

[00:03:00] and your radiator hoses for any leaks. Keep in mind that you may need to get the fluid hot to expose the leak. If that's necessary, be careful not to burn yourself on any hot components. Because of the sweet smell, animals and even toddlers can confuse this fluid with something safe to consume, so don't leave any drops to chance. Brake fluid leaks are pretty easy to spot because they're commonly found dripping on the inside of the rims, down the tire and on the ground near the brakes. Brake fluid is clear and can become amber color over time. This is extremely corrosive

[00:03:30] and will eat through paint quickly so be mindful to avoid transferring the fluid from your hands to the paint by mistake. Brake lines can wear out or get pinched or punctured over time, creating a soft or spongy pedal feel. Check your master cylinder and fill it up if it's low. Then visit your mechanic immediately as this is a major concern. Oil is probably the most common leak as it has the most potential fail points on the engine. It's somewhat thick and greasy

[00:03:59] and amber to dark brown depending on its age. Check your dipstick to try to match the color and smell. If you think it's the culprit, use a flashlight and search any obvious leaks to help your mechanic pinpoint the issue, saving him time and you money. Finally and possibly most concerning is a gas or fuel leak. You're likely to smell the leak before you see it because fuel is volatile and evaporates quickly. Look under the vehicle for long thin lines running from the gas tank all the way to the front of the car. These can become rusted and brittle over time.

[00:04:30] Call your mechanic immediately and avoid leaving your car indoors overnight. For quick and easy clean-ups use kitty litter, sawdust or oil dry absorption clays. Likewise if the leak continues, you can lay cardboard, plastic drop cloth or a paint mat to absorb the drips. But again, you need to get this addressed immediately from a professional mechanic. Quickly diagnosing which fluid is leaking from your car will help you determine what and where the leak is coming from

[00:05:00] and if you need to seek a mechanic immediately or if there's no concern at all. For more how-to car repair videos, visit I'm Larry Kosilla from As always, thanks for watching. (techno music)

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