Why Does My Convertible Top Smell Musty or Moldy?

A convertible top smells musty or moldy because moisture is trapped somewhere it can't dry out. The usual culprits are a top that was folded down while still damp, clogged drain tubes that let water pool in the top storage well, worn seals that leak into the carpet, or mildew growing in the fabric itself. Find the moisture, dry it out, and clean the affected area, and the smell goes away.

This is the most common cause. Folding a damp top packs wet fabric into a dark, closed storage space, which is perfect for mildew. Even dew or a quick rinse is enough if the top gets stowed for a few days.

Convertibles have drain channels and tubes that carry water away from the top's storage area and from around the windows. Leaves, dirt, and pine needles clog them. When they back up, water pools in the storage well or overflows into the trunk and the carpet behind the seats, which are places you'd never think to check.

The rubber seals around the top and windows dry out and shrink with age and sun, especially in Southern California. Small leaks let water in during rain or a car wash, and it soaks into the carpet or seat foam without you seeing it.

Fabric tops (canvas or similar cloth) can hold moisture in the weave. Dirt and organic debris give mildew something to feed on. You'll often see dark spots or a gray haze on the fabric, especially along the folds.

Water from any of the above ends up in the carpet and the foam pad underneath, and that's where most of the smell actually comes from. Check behind the seats and in the rear footwells.

1. 1.Smell around the car. Is it strongest at the top, the rear seats, or the trunk?
2. 2.Press hard into the carpet, especially behind the seats and in the footwells, and feel for dampness
3. 3.Open the top storage area (with the top up) and look for standing water, dampness, or debris
4. 4.Inspect the fabric for dark spots or a gray haze, especially at the fold lines
5. 5.Check the seals for cracks, gaps, or flattened sections
6. 6.Find the drain openings (your owner's manual shows where they are) and clear any debris

Dry it out first. With the top up, park in the sun with the windows down on a dry day. Pull up wet carpet where you can, and use a wet/dry vac and fans on damp areas. Nothing else will work until the moisture is gone.

Clear the drains. Gently run trimmer line or a flexible drain cleaning tool through the drain tubes, then pour a little water in to confirm it flows out underneath.

Clean the fabric top. Use a cleaner made for convertible fabric tops and a soft brush. Work in straight lines, rinse thoroughly, and let it dry completely before lowering it. Avoid household cleaners and pressure washers, which can damage the fabric and the stitching. For vinyl tops, use a vinyl-safe cleaner.

Re-protect the fabric. After cleaning, apply a fabric top protectant to restore water repellency so the top sheds water instead of soaking it up.

Deep clean the cabin. Shampoo and extract any carpet or seats that got wet, then dry them fully.

• •Never lower a wet top. Let it dry in the sun first, even if it's just morning dew
• •Clear the drains a couple of times a year, and before the rainy season
• •Treat the seals with a rubber protectant so they stay flexible
• •Re-apply fabric protectant about once or twice a year
• •Don't run the car through brush washes. They wear the fabric and force water past the seals. Hand washing is safest

If a seal is torn, the fabric is ripped, or water keeps getting in after the drains are clear, take it to a convertible top shop. No amount of cleaning fixes an active leak. If mildew has spread into the top's inner lining or headliner, the top may need professional cleaning or replacement.

For the cabin side, our Gold Detail includes shampoo extraction of carpets and seats plus steam cleaning of hard surfaces, which gets moisture and mildew out of the interior where most of the smell lives. For more on general car odors, see how to get rid of a musty smell in your car. Book online or call (310) 692-4495.