Cold clutch doesn’t want to work properly

Dear Car Talk:

I have a 2013 Hyundai Accent with a six-speed manual transmission. When the temperature drops below 40 degrees overnight, the next morning, my clutch doesn't respond properly. After starting and shifting into reverse, I can have my clutch to the floor and I still can't shift out of gear or stop my car from moving backward. If I stop the car using the brakes, it kills the engine, just as if I had tried to stop with the clutch completely out. If after stalling I pump the clutch three or four times, the car runs perfectly for the rest of the day. I have only 2,000 (yes, two thousand) miles on the car. I'm 75 years old and have never owned a car, truck or motorcycle that I didn't have to shift manually, so I know how to use a manual transmission. The service department at the Hyundai dealership where I purchased the car new can't find the problem and correct it. Do you have any ideas? Thanks. – Hugh

RAY: Sure. Years ago, a customer came into the shop with a similar complaint. After running up his repair bill for a few hours, we finally discovered that he had two sets of floor mats in the car. Because they were bunching up behind the pedals, they prevented him from pushing the clutch all the way to the floor. So we tossed them in his trunk, charged him $300 and sent him away happy.

Not really. We only charged him $280.

Since you have so many years of experience driving stick shifts, Hugh, I’m going to guess that’s not your problem. But check.

If your floor mats are not guilty, and if you’re not actually leaking hydraulic fluid, I’d ask your dealer to swap out your clutch master cylinder. There may even be a technical service bulletin on it by now.

Clutch master cylinders often fail this way in cold weather. If the seals around the plunger are failing, they can shrink a little bit in cold weather and allow the hydraulic fluid to bypass the plunger. That creates insufficient pressure to disengage the clutch. Once everything warms up, the seals expand enough to do their job, and the clutch works fine again – until the next cold start.

Since you’re under warranty, I think you should politely insist that they replace the clutch master cylinder. They owe it to you to try something, and that’d be my first guess. Plus, it’s the cheapest thing for them to try.

If that doesn’t fix it, then unfortunately – for the dealer – the problem is the clutch itself, and they’ll owe you one of those, too.

You don’t say whether the dealership has actually witnessed the problem, Hugh. It might be that they don’t believe you. You don’t wear your tinfoil hat to the dealership, do you?

Since it’s a predictable problem, I would advise you to leave it with them overnight on a night when the temperatures will be low enough to make the clutch fail. You might even come back in the morning when they open so that everyone can witness the clutch failure together. Once they’ve experienced the failure themselves, they’ll be obligated to fix it for you.

Just remind them not to store your car in their heated garage overnight, Hugh. Good luck.

When convertible will sit for extended time, leave the top up

Dear Car Talk:

I have a VW convertible that I leave garaged in Florida for eight months. Is it better to leave the top up or down when I am gone? – Frances

RAY: Gee, Frances, I'm trying to figure out why you'd want to leave the top down. Maybe to keep the car aired out? So it'll smell musty, like your garage, when you get back?

The top is designed to keep things out of the car – not just rain, but dust, debris and the occasional iguana falling out of a tree. So I’d be inclined to secure the top and let it do its job.

While it’s unlikely to rain in your garage, the car certainly will fill with dust. Mice, spiders, centipedes, larvae, scorpions or lost Boy Scouts aren’t out of the question, either.

Plus, we’ve seen some convertible tops get creased if they’re left down for a long time. You can always un-crease them by putting the top back up for a while, but sometimes the color changes a little bit where the roof is stretched and folded.

And given that I can’t come up with any really good arguments for leaving the top down, I’d say secure the car and leave the top up, Frances.

Visit the Car Talk website at www.cartalk.com.

About the Author