2010 Ford Fusion Hybrid: Stuck Throttle Near-Miss, For Real
April 19, 2010
I had a stuck-throttle unintended acceleration incident on the way to work in our 2010 Ford Fusion Hybrid. No, I am not making this up. It was not a set-up. It was not a planned test. I was simply driving to work listening to the radio, somewhat groggy and in need of caffeine at 5:45 in the morning, when it just happened.
The whole thing lasted only a handful of seconds before it self-corrected. There was no crash, but the Fusion did bear down uncomfortably close to the car ahead after I lifted my foot off the throttle at the end of a passing maneuver.
There's a video after the jump. Skip all the way to the end if you don't want the back-story. For those who do, here's how it went down...
By now, everyone should know that a stacked floor mat can't engage the floor hooks because the mat below is hogging them. Unsecured floor mats can drift forward toward the pedals where, if the position is just right, they can contact the throttle pedal when the driver floors the throttle. If the mat is stiff or inflexible enough, as some Toyota/Lexus all-weather floor mats have proved to be, the throttle can be trapped in the fully open position (or near enough as makes no difference). I've duplicated this scenario in controlled conditions with a Toyota Prius and Lexus ES350, but it had never happened to me, for real, with my guard down.
For this reason I personally removed the driver side winter floor mat from our Ford Fusion Hybrid weeks ago and stashed it in the trunk. But recently, a mechanic or car-wash attendant must have found it there and reinstalled it, trying to be helpful. I didn't notice this until I stepped out of the car when I got home.
I wasn't too terribly concerned because my previous test-fit of the Ford Fusion's floor mats left me with the impression that Toyota/Lexus-style pedal entrapment couldn't happen in this car. The geometry of the pedal and floor seemed different, somehow.
Still, this was going to be good blog fodder. I would photograph the mat sitting on the carpet and fashion a blog post featuring rude comments about the automotive service industry not "getting it" despite mountains of publicity, and that would be that.
I took my pictures at the curb in front of my house and messed with the throttle by hand as I had weeks before, once again unable to find the "sweet spot" that would make one really stick to the other. As before, it seemed like no big deal.
At that point the dinner bell rang and I went inside. Time passed. I watched some TV with the kids and forgot all about the Fusion and failed to go back outside and re-remove the mat and toss it back in the trunk.
Smash-cut to the 405 freeway at 5:45 am the next morning, halfway to work. I mashed the throttle to pass a slow-moving vehicle by shooting into a gap in traffic in the lane to my left. Lane change accomplished, I relaxed my foot to settle in but the car kept accelerating (unintentionally, at this point) for perhaps another two or three seconds. Just as the Fusion bore down to within a couple car lengths of the car ahead, I heard a click down by my feet and the pedal released, returning all to normal.
It all happened fast and I didn't actually figure out what had happened until after it was over. Experimentally, I tried it once more with clear road ahead and the same thing happened: the throttle hung open for a couple of seconds until something down by my feet clicked and the throttle returned to idle.
At this point I knew it was the floor mat, and I resolved to keep the accursed thing right where it was for pictures and video at the office. I drove carefully the rest of the way to make sure I came nowhere near full throttle and a repeat performance.
Apparently, my earlier tests of the Fusion didn't replicate the Lexus 350 condition because I was out of the car and using my hand to operate the throttle. Turns out the downward weight of a foot aggrivates the problem by not allowing the mat to bend up out of the way. If this happens to you, lift both heels up, kick backwards and reach down and tug the mat backwards.
Moral of the story: don't assume everything is OK because a) you don't drive a Toyota/Lexus product or; b) because everything looked OK in a random curbside test. The real world contains far more variables and conditions than you or I can account for. This incident suggests the brand of car may be irrelevant.
Don't stack floor mats. Make sure the one you're using is properly hooked. Take the one you're not using out of the car. And don't simply toss it in the trunk, because I've discovered that this is no guarantee.
Dan Edmunds, Director of Vehicle Testing