Car Stopped Functioning Whilst Rolling, Anyone Know Why?

SquirrelMadness

SquirrelMadness

SquirrelMadness

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Driving down country lane, about to go up a little hill at around 30mph... engine light came on, steering stiffened (very stiff, almost couldn't steer) and brake stiffened to the point where you had to press it really hard to brake. Gas didn't work at all.

I let the car roll to a stop up hill, then rolled back down the hill backwards and just managed to steer it into a small off-road parking space. Lucky no cars and VERY lucky there was traffic on the usual motorway route hence why I was on country lane.

Started car again after 10 minutes of waiting... brake immediately loosened almost like a deflating balloon, steering loosened, no engine light... drove home.

Anyone know what caused this? Car: 2001 Ford Focus.

Thanks.



EDIT: Decided to test the battery today. Initially looked fine until I took it out to clean the terminals (steel wool) and put it back together...


Check the last half of video where car just struggles to start.

Pics of battery when I took it out:

2OSomol.jpg

z6xUP4O.jpg
 
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Was the engine lumpy when it started back up? I had a coil pack go and it started having an issue like this and the engine was way down on power.
 
When your engine light came on it meant the engine had stopped working it was not running basically.

The engine running produces vacuum or electric power to power the brakes, and runs a hydraulic pump or electric pump to power the steering.

Once you got your engine running again after the wait then the power came back for your steering and brakes.


The question you really want to answer, is why did your engine stop running?

That can only really be answered by taking to a garage and getting the fault codes read, unless you or a friend can do that.
 
Entai said:
When your engine light came on it meant the engine had stopped working it was not running basically.

The engine running produces vacuum or electric power to power the brakes, and runs a hydraulic pump or electric pump to power the steering.

Once you got your engine running again after the wait then the power came back for your steering and brakes.


The question you really want to answer, is why did your engine stop running?

That can only really be answered by taking to a garage and getting the fault codes read, unless you or a friend can do that.
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Are you sure about that?

Brakes, as far as I'm aware brakes are hydraulic systems assisted by vacuum. On every car I've had even after engine shut-off the brakes have worked as normal for at least 1-2 uses of the brake pedal before it hardens, however even after that brakes will still work with a little more force.

Steering is usually either a belt or electric motor driven hydraulic pump. With engine shut off it's still possible to turn and from experience if you're still moving it's a little easier than stood still.

If the brakes hardened immediately then I'd be looking for a vac leak. Such a leak could in principle cause engine shut off, depending on severity of said leak.
 
Resident said:
Are you sure about that?

Brakes, as far as I'm aware brakes are hydraulic systems assisted by vacuum. On every car I've had even after engine shut-off the brakes have worked as normal for at least 1-2 uses of the brake pedal before it hardens, however even after that brakes will still work with a little more force.

Steering is usually either a belt or electric motor driven hydraulic pump. With engine shut off it's still possible to turn and from experience if you're still moving it's a little easier than stood still.

If the brakes hardened immediately then I'd be looking for a vac leak. Such a leak could in principle cause engine shut off, depending on severity of said leak.
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OP said they stiffened to that point, I didn't read it as they suddenly lost vacuum assistance. Even with a massive vacuum leak, the servo would still function and assist the brakes as it has a non-return valve on it's connection with the inlet manifold (also you'd loose vacuum assistance when there's no or little vacuum when at high throttle levels). Even with a massive vacuum leak I can't see that abruptly stopping the engine, on a petrol engine it'd just be like opening the throttle fully and diesels don't generally have vacuum in the inlet manifold (they control engine speed by metering the fuel, not air). They have an electric (iirc this is most common) vacuum pump to assist the brake servo.

Loosing steering assistance unexpectedly will make the steering feel very wrong and stuff, yes it will be easier than dry steering - but it's far to say it'll be stiff.

SquirrelMadness said:
I've been told that it might be a battery issue... could a battery cause this to happen? It would more likely be the alternator or battery and alternator in combination right?
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I'd be looking here too, check the battery terminals are on tight and that any earth straps are tight and in good order. If the battery had disconnected for a small amount of time, that could be enough to stop the engine as you've described.
 
SquirrelMadness said:
I've been told that it might be a battery issue... could a battery cause this to happen? It would more likely be the alternator or battery and alternator in combination right?
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I had this sort of thing in a company car that had to have an engine change from new. Was a simple loose terminal on the battery that the dealer couldn't find after several visits. I just turned the terminal connector around a bit and tightened it up to get a solid connection, and no problem from then on.
 
My old VW used to do this occasionally. Diagnosed as a failed crank sensor, so the engine got confused as to which way was up which affecting the timing and it would cut out. Slightly alarming at 60mph on a motorway slip road when you lose power assistance for the brakes and steering. As you found out today.

Get it plugged in and get the codes read.
 
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Why the hell do car manufacturers do this, or are even allowed to do this?

The fact that if your engine/electrics on a car fail it can affect your brakes is insane.
 
Had a Fiesta that lost power* altogether and was pretty much identical to what you described. I'd say take it to a garage though and get it checked out, wouldn't want it happening again at 70mph on the motorway.

*Was replacing a steering wheel and didn't connect the battery terminals properly, completely my own fault.
 
BUDFORCE said:
Why the hell do car manufacturers do this, or are even allowed to do this?

The fact that if your engine/electrics on a car fail it can affect your brakes is insane.
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Your brakes still work you just have no assisted power. So like a F1 car you have to do all the work. When you PAS goes then the steering will feel VERY heavy as your also fighting the power rack so will feel a lot "stiffer" than a car with no PAS.

Disclaimer for some RR and Citreon Xantia's...

I watched a brand new RR being reversed off a transporter. The driver started it up and immediately started to reverse. Without giving the braking system enough time to "charge".. It was ok though a brand new Rover 827 Sterling stopped it.....Yeah it was a while ago
 
mattyg said:
Your brakes still work you just have no assisted power. So like a F1 car you have to do all the work. When you PAS goes then the steering will feel VERY heavy as your also fighting the power rack so will feel a lot "stiffer" than a car with no PAS.

Disclaimer for some RR and Citreon Xantia's...

I watched a brand new RR being reversed off a transporter. The driver started it up and immediately started to reverse. Without giving the braking system enough time to "charge".. It was ok though a brand new Rover 827 Sterling stopped it.....Yeah it was a while ago
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Fair enough, I don't like the idea though, my motorcycle the brakes are 100% mechanical work just as good when the bike is off. Much prefer that.
 
BUDFORCE said:
Fair enough, I don't like the idea though, my motorcycle the brakes are 100% mechanical work just as good when the bike is off. Much prefer that.
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That's because the hydraulic system on motorcycle brakes is much smaller. To have no vacuum assistance on a system the size of car's hydraulic braking system, you'd need a massive master cylinder and pedal. The servo on a car's system just amplifies the mechanical effort put in to the system by your pedal.
 
BUDFORCE said:
Why the hell do car manufacturers do this, or are even allowed to do this?
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The brakes still work, it's not a critical safety failure. There's a loss of power assistance from the servo after a couple applications and the driver has to exert more effort. It's not a new thing, cars have been running the same system for 50+ years.
 
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