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Uncontrollable sudden acceleration

My 2008 Volvo s60 did this in not one but two directions Volvo sent a corporate engineer but he found no problems but the also refused to check the ECM even after I insisted that this car always had low voltage isssues HELP

There is a web site for the national highway safety commission, you should report these events to them.

Uncle Turbo is referring to The National Highway Traffic Safety Administration (NHTSA).

Here is a link to the portion of the NHTSA website that allows you to report safety problems:
https://www-odi.nhtsa.dot.gov/ivoq/index.cfm

You can also search for complaints. There are 3 complaints against the 2008 S60. Two are floor mats that won’t stay in place (same person complained twice) and the other is a surge like yours. Both complaints were in 2010.

Do you have a consumer protection radio show in your area? In my area at least there are a couple of reporters that specialize in consumer protection issues. They have a radio call in show and folks like you who’ve not been satisfied with a consumer problem will call in and explain the problem. The reporter of course can’t fix it on the radio, but the vendors are aware of this show and are very responsive when the reporter calls the vendor following week and asks what is going on.

Try removing the driver’s side floor mat. I know you might find it hard to believe the floor mat did this, but removing it will at least rule it out as a cause.

I never believed a floor mat might cause this problem, until it happened to me in an RV.

Also, practice shifting into neutral and bringing the car to a stop, so next time this happens, you’ll know exactly what to do.

I’ve seen bad motor mounts do this but that was on much older cars. Basically the engine being allowed to twist more than normal pulled the accelerator cable, opening up the throttle body and causing the engine to rev up.

I agree with RemcoW, have a knowledgable Volvo mechanic check the accelerator cable, the pedal and motor mounts. Either at a reputable dealership or find a knowledgable independent Volvo mechanic.

Strange things can happen to cars as they get older. Now, in regards to pressuring Volvo via the NHTSA or a consumer reports program, I don’t think that will work. Your car has been on the road for five years and there are no patterns of Volvo’s doing this. As cars get older, they can do odd things. If you searched enough, you probably find every car model ever produced will have one or two reports of this type of problem. Its a maintenance issue, not a design issue.

After five years, instead of a faulty thermostat, you have this issue. Know what to do if it happens again, but above all, find a Volvo gear head that can go through it and verify that everything is tip top on maintenance.

Also, when you have a mechanic knowledgable about Volvo’s look at it, let them know if the car has ever been in any crashes, had any level of water damage, or has ever had after market performance enhancement chips installed in it. The more information they have, the more likely they are to determine what’s going on.

This car should be drive by wire and if no codes are present one could make a wild guess that the problem could be caused by a sticky throttle plate.
This is where induction cleaning could possibly help and of course, Whitey’s suggestion about removing the floor mat is a good idea.

The mats in my Lincoln have a loophole to attach to a hook on the floor to prevent this kind of problem but the mat has also come off of the hook a few times and gotten bunched up underneath the pedals.
While it never snagged the accelerator pedal, it has caused my foot to snag and inadvertently blip the throttle.