Car suddenly stopped

Common causes of stalling are the crankshaft position sensor and camshaft position sensor. They often fail when they get warm. There should be a diagnostic fault code stored in the Engine Computer that will lead to the circuit or system with the problem, not necessarily the defective part. A stuck-open EGR valve can cause stalling too. It normally only opens at higher speeds and when the engine is warm.

There is nothing that should affect the gas pedal getting hard to push so I don't have an answer for that, but there should be enough reserve in the power brakes to allow for two or three pedal applications to get the car stopped. After that, the pedal will be hard to push, but not impossible. You might need two feet. To see what that feels like, you can experiment in a vacant parking lot, (where I'm not around :) ), and try braking a few times after turning the engine off. Without that experience, the surprising loss of power assist can cause a driver to panic and lose control of the car. You will never lose total braking from a stalling engine.

Caradiodoc

Yup. You no longer have power steering when the engine stalls because the pump isn't running. It's belt-driven by the engine. You have "armstrong" steering. Get it? :) Strong arm? Oh well.

There is still the mechanical steering linkage that will not be lost. Also, for reference, you will likely not even notice the lack of power steering assist at highway speeds. Many newer cars actually have a computer-controlled valve the in effect turns off the power steering at higher speeds to save engine power and improve fuel mileage. You really only need the power assist at very low speeds because you are trying to scrub the tires against the ground when you try to turn them. When the car is moving, the tires are free to turn when they are rolling.

A lot of really big heavy cars from the '60s and before didn't have or need power steering. As it became more common to drive at current highway speeds an alignment angle called "caster" was increased to greatly improve directional stability and steering wheel self-return after turning a corner. Caster is what makes the wheel come back to center when you let go of it. But increasing caster causes the tire to push down when turning which makes the corner of that 3000 pound car lift up. When you turn left, for example, the left corner of the car will raise up a little. THAT'S why they added power steering to cars. It was to allow a higher caster setting to make it real easy to keep the car going straight without constantly correcting the steering wheel. The drawback to higher caster is that it makes it real hard to turn the wheels at low speeds without power steering.

I'm not suggesting you do anything dangerous, but if you were to carefully shift to neutral while driving at highway speed, (please be careful you don't pop it into reverse), then turn the ignition switch off, you will see that you can steer quite easily yet until the car slows down. You won't be able to turn the key far enough to lock the steering wheel because it has to be in "park" to do that.

For anyone else reading this, be aware a lot of older rear-wheel-drive cars use a vastly different type of steering gear box that has a lot of play in it. That play is taken up by the pressurized power steering fluid when the engine and pump are running. When those engines stall, the car will usually veer to the right, (roads slant to the right so rain will run off), and you have to counteract that by turning the steering wheel almost 1/4 turn to the left. You will still have steering control. It just won't be much fun driving that way. Newer front-wheel-drive cars since before the '80s have rack and pinion steering systems. They don't have that play built in so nothing happens to steering wheel position when the engine stalls.

Caradiodoc

If a sensor is failing it will eventually quit running completely and won't restart. Those sensors do often become heat-sensitive and will work again after they cool down for an hour. It's actually a lot easier to diagnose once it becomes a permanent "no-start". When it's intermittent such as you have now, there is never a fool-proof way to know if it is fixed. You can only know it is NOT fixed if it acts up again. That is one of the frustrating things about being a conscientious mechanic. They want to do the best job possible and end up being unable to solve the problem or know if it will be solved by the work they just did.

I can share too that my rusty trusty '88 Grand Caravan failed to get me home about a month ago for the first time in its life. Needed a friend to rescue me with a trailer 40 miles from home. The good news is I had been fighting this intermittent stalling problem for 11 months! And the cause absolutely had nothing to do with the symptoms. It was the last part anyone would think to look at until the problem became permanent. Runs REAL good now!

Basically you don't want to drive your car with this problem any further than you are willing to walk, either to home, work, or an ice cream stand. It could go on like this for years, but it could also stop running in the middle of the freeway tomorrow. Now that I scared you, when the stalling IS due to a heat-sensitive sensor, they often work fine on the highway because of the air flow over the engine, then quit shortly after slowing down when there is less air flow.

I should mention too that when a sensor fails while driving, the Engine Computer will detect it and set a diagnostic trouble code in memory. Your mechanic will read those codes which will lead him to the circuit or system with the problem, not necessarily the defective part.

Caradiodoc