Rear ended myself ?!?

[Lil Red Broncette]

Of course I didn't, but it sure felt like I got rear ended. The car behind me was easily 20ft away. No damage nor marks. Puzzling.

So here are the details. I was at a stop sign of a T intersection. I let off the brake and gave gas to creep from the stop line up to where I could see crossing traffic better in preparation of pulling out . Because I was on a very steep incline, I had to give me more gas than usual to get it move. I saw a car coming decided to wait rather than rush it and switched to the break and then there was a bang and the car rocked.

My first thought was that the car behind me rear ended me when I aborted my pulling out, but I immediately looked in the rearview mirror and they were stopped far enough back I could see road between me and them. They hadn't moved and there wasn't time for them to have rolled back.

What I think happened was a combination of the car doing things all at once. Like maybe starting to shift gears just as I let off the gas and inertia on the drive train from the sift just as I hit the brakes? I've experienced odd/hard auto trans shifts in other cars from making big throttle change just as it was shifting, but this was far harder than anything I experienced before.

I also want to say it seemed like the engine tried to auto stop but did an auto restart before it stopped completely. But I shouldn't have been stopped long enough for auto stop to kick in.

I wonder...could the auto trans have gone from a torque converter slip to a locked in gear state just as I took my foot off the gas and then because of my quick stop not allowed slip and acted like a manual trans when the clutch had not been pushed in when coming to a stop hence the near stalling/restart sort of feeling?

In any case it was the darndest thing I experienced.

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[Rjacks258]

Strange. But I vote for the auto start slightly stopping and starting.

 

[2020FordRaptor]

Of course I didn't, but it sure felt like I got rear ended. The car behind me was easily 20ft away. No damage nor marks. Puzzling.

So here are the details. I was at a stop sign of a T intersection. I let off the brake and gave gas to creep from the stop line up to where I could see crossing traffic better in preparation of pulling out . Because I was on a very steep incline, I had to give me more gas than usual to get it move. I saw a car coming decided to wait rather than rush it and switched to the break and then there was a bang and the car rocked.

My first thought was that the car behind me rear ended me when I aborted my pulling out, but I immediately looked in the rearview mirror and they were stopped far enough back I could see road between me and them. They hadn't moved and there wasn't time for them to have rolled back.

What I think happened was a combination of the car doing things all at once. Like maybe starting to shift gears just as I let off the gas and inertia on the drive train from the sift just as I hit the brakes? I've experienced odd/hard auto trans shifts in other cars from making big throttle change just as it was shifting, but this was far harder than anything I experienced before.

I also want to say it seemed like the engine tried to auto stop but did an auto restart before it stopped completely. But I shouldn't have been stopped long enough for auto stop to kick in.

I wonder...could the auto trans have gone from a torque converter slip to a locked in gear state just as I too my foot off the gas and then because of my quick stop not allowed slip and acted like a manual trans were the clutch had not been pushed in when coming to a stop hence the near stalling/restart sort of feeling?

In any case it was the darndest thing I experienced.

That is extremely odd. Probably was auto start stop.

 

[Lil Red Broncette]

Strange. But I vote for the auto start slightly stopping and starting.

That is extremely odd. Probably was auto start stop.

I've had that happen a few times before without the other stuff and it seemed tame. Nothing like this.

 

[Moto26]

Strange. But I vote for the auto start slightly stopping and starting.

No way was it the ASS. It takes several seconds of sitting motionless for that to activate.

I blame all the computer-controlled electronic functions that don’t respond well to unusual input from the driver. My Bronco acts weird like this sometimes, and so does my truck.

For example, at my post office you exit the parking lot on a steep uphill, but before you get to the stop sign for the main street, there’s a crest. Sometimes, when I accelerate briskly up the hill, but then I have to stab the brakes for a pedestrian or something, I will get a weird lurch. This happens in both vehicles.

These modern vehicles don’t seem to like any sudden gas-to-brake (or vice-versa) movements…

 

[PG_Bronco]

Hard top? I had a loud pop occur a few weeks ago and couldn’t figure it out until I noticed this (pic below, behind driver side rear door). Was driving on highway and guessing the top stressed the bolt too much that secures the hardtop. Dealer can’t get me in until 2/27, which is ridiculous…

 

[Lil Red Broncette]

Hard top? I had a loud pop occur a few weeks ago and couldn’t figure it out until I noticed this (pic below, behind driver side rear door). Was driving on highway and guessing the top stressed the bolt too much that secures the hardtop. Dealer can’t get me in until 2/27, which is ridiculous…

Yes, a 2DR hard top. This involved a very definite rocking of the vehicle, which I can see being caused by something drive train-y, not what I would expect from a stress dent or panel giving but I should expand search outside the rear area.

 

[Lil Red Broncette]

I blame all the computer-controlled electronic functions that don’t respond well to unusual input from the driver. My Bronco acts weird like this sometimes, and so does my truck.

For example, at my post office you exit the parking lot on a steep uphill, but before you get to the stop sign for the main street, there’s a crest. Sometimes, when I accelerate briskly up the hill, but then I have to stab the brakes for a pedestrian or something, I will get a weird lurch. This happens in both vehicles.

These modern vehicles don’t seem to like any sudden gas-to-brake (or vice-versa) movements…

Your situation at the post office is pretty much the same conditions.

I agree about not responding well to sudden changes in conditions. My profession involves writing software for controlling hardware. While not a car, there are always some transitional conditions like shifting gears in a trans where the software has handle. Because such event is transitory and normally isn't interrupted the software writers often don't address the "what if conditions change in the middle" case. So when things do change suddenly, like gas to break, the software continues with the action like shfiting gears until it is done with the shift. Only then does it recognize the changed conditions, but till then it may be doing things totally wrong for the changed condition.

 

[JimboSlice]

Of course I didn't, but it sure felt like I got rear ended. The car behind me was easily 20ft away. No damage nor marks. Puzzling.

So here are the details. I was at a stop sign of a T intersection. I let off the brake and gave gas to creep from the stop line up to where I could see crossing traffic better in preparation of pulling out . Because I was on a very steep incline, I had to give me more gas than usual to get it move. I saw a car coming decided to wait rather than rush it and switched to the break and then there was a bang and the car rocked.

My first thought was that the car behind me rear ended me when I aborted my pulling out, but I immediately looked in the rearview mirror and they were stopped far enough back I could see road between me and them. They hadn't moved and there wasn't time for them to have rolled back.

What I think happened was a combination of the car doing things all at once. Like maybe starting to shift gears just as I let off the gas and inertia on the drive train from the sift just as I hit the brakes? I've experienced odd/hard auto trans shifts in other cars from making big throttle change just as it was shifting, but this was far harder than anything I experienced before.

I also want to say it seemed like the engine tried to auto stop but did an auto restart before it stopped completely. But I shouldn't have been stopped long enough for auto stop to kick in.

I wonder...could the auto trans have gone from a torque converter slip to a locked in gear state just as I took my foot off the gas and then because of my quick stop not allowed slip and acted like a manual trans when the clutch had not been pushed in when coming to a stop hence the near stalling/restart sort of feeling?

In any case it was the darndest thing I experienced.

That happened to my wife the day she drove her new Audi Q7 home. She called me and said she was just rear ended and the other car just took off, LOL. It was the auto stop/start.

 

[stickshifthappy]

Dammit.... these click bait posts !! Sorry that sucks. I hate hearing about, and worse seeing images of damages Broncos.

 

[swami37]

Loose nut behind the wheel.

 

[JerryC]

Any chance the tailgate wasn't fully latched?

 

[Lil Red Broncette]

Any chance the tailgate wasn't fully latched?

zero

 

[KABQ]

My auto sometimes makes oddly aggressive 1-2 and 2-1 shifts where it will pull really hard against the brakes, especially when cold. Doesn't explain the noise, though...

 

[HeliPilot]

Don’t these have hill start stop assist. Maybe it decided to lock the brakes down.

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