Car hits invisible parked car

So here’s the story. I pulled into someone else’s driveway to turn around in a neighborhood. While I was backing out (coasting) the car came to a violent stop to the point that both mine and my wife’s head hit the headrests. It felt exactly like I backed into something. Looking behind me again, I find that there is nothing there and I’m still a good 10 feet from the curb on the other side of the road. The road is empty. The car behaves normally after that. I should also mention in case this is a transmission issue, that there is a whining noise coming from somewhere outside the car when I’m in gear and moving. So did I just find where Wonder Woman parked her jet or is something going to break soon?

Make, model, year? Auto or manual trans? Any chance the trans was shifted to Park or Drive from Reverse while moving? Does the whining sound chance in pitch when the steering wheel is turned? Have you checked the level of the Power Steering fluid? How old is the serpentine belt?

Ed B.

It would help to know what kind of car and transmission.and were you in reverse or neutral. If you were in reverse and your linkage is not in adjustment ( automatic ) it is possible it hit park. If you are going slow enough it will engage.

Sorry for the omitted information. It’s a 2003 Oldsmobile Alero 4-cyl with an automatic transmission. My hand wasn’t even on the shifter so I’m sure I didn’t shift it out of reverse. The whining sound is only related to actual RPMs in motion. Power steering pump was already replaced as a suspect for the whining noise. Serpentine belt is about 30,000 miles old.

have tried backing up since?

Yes I have. I drove it to work today since I have no other means to drive 50 miles. I didn’t notice anything more unusual than usual.

How old are you? At any point did you get out of your car to see if you hit some hidden object?

I’m an irrelevant 32 years old, but I did walk in the unoccupied space, look around, then backed into it again with no result.

have you checked you parking brake to see if it still works? maybe it locked up and possibly broke cable

I haven’t, but the stop was far too sudden to be a braking issue I believe. Plus, the parking brake has always been weak on this car anyways.

if its weak something could have come loose and jammed up. prob not but its free to check

reversing and braking does tighten self adjuster on some cars rear brakes

does your gear indicator point directly to D , R , N etc? ifnot linkage could be out of adjustment

It’s an electronic indicator on the dash, and the actual shifter has no indicator

I had a 1982 malibu do something similar. It locked up and then seemed to be OK after I put it in neutral. I drove about 50 miles before it locked up again. I dropped the pan and found bearings in it. Apparently, some of the bearings were circulating around and jammed up the gears.

You may want to take this to a reputable tranny shop for a look-see. The only thing I can think of that would cause the sudden lockup you describe would be a parking pawl, and while I cannot for the life of me imagine how that could suddenly engage while in reverse, the whining would suggest that something is definitely wrong. You don’t want your drivetrain to suddenly jam up while you’re driving, so I strongly recommend that you get this checked out ASAP.

Alright. I will be taking it to the mechanic today. Thanks for the opinions!

A binding one way clutch in the transmission, sometimes called a “sprag” can cause this.

I wasn’t suggesting that YOU shifted out of reverse but if your shift mechanism is worn or out of adjustment the normal flexing of the cars body when turning up a driveway could make it happen.

I’m leaning too towards the parking pawl.
Maybe things are worn just enough that you had it between Park and reverse…though it showed Reverse on the dash indicator.
I had one that was just a little out of adjustment. I hopped out thinking I was in Park…walked into the house…and came back to find my truck in the neighbors driveway. Good thing both their car were gone.

A little adjustment and it fixed it.

Yosemite