Stalls while driving

I stalled while driving and it would not restart . Had to be towed to my mechanic. He said I need a new air conditioner compressor. I do not understand what this has to do with the engine shutting down. Thanks!

My car has 94000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
The only way I can think of that the air compressor would be able to shut the engine down is if the pulley on the compressor locked up causing the belt to break. The belt breaking is what would cause the engine to eventually shut down. I would recommend having your vehicle inspected by a qualified professional to determine the exact cause of this issue. This may include a fuel pressure test, alternator/battery test, as well as a good visual inspection.

How to Identify and Fix Common car Problems ?

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If the engine stalls as you are driving, it can put you and your passengers in danger. Engine stalling can be unexpected and happen at any time if the warning signs of trouble are left unchecked. The reasons behind engine stalling include a bad battery, moisture in the gas, and other electrical issues.
Common reasons for this to happen:

Low fuel pressure, dirty or defective fuel injectors, or broken fuel pump: The fuel pump is responsible for transferring fuel from the tank to the engine.

The most common reasons an Audi A4 engine stalling are the fuel system, the air intake system, or the ignition system. Search our network of RepairPal Certified shops near you to speak with a technician about your issue.
Most commonly when the car stalls while driving, but starts right up after, the cause is an intermittently failing crankshaft position sensor or camshaft position sensor. The first step to diagnosing this problem however, would be to scan the engine control module to check for fault codes.
Immediately turn on the vehicle`s hazard warning lights. They`re the universal sign of distress. If you`re unable to pull completely over onto the shoulder, or if the car is stalled in a traffic lane, do not attempt to get out of the car! Similarly, never try to cross a highway on foot.
Common culprits include a faulty fuel pump or fuel pump relay. A clogged fuel filter or bad fuel pressure regulator is also common on return-type fuel systems. Another often overlooked problem is the vehicle simply being out of fuel. Sometimes the fuel gauge breaks or is inaccurate.
Auto Start/Stop Technology automatically shuts off the engine when the vehicle comes to a full stop and idles for more than a few seconds. Once the driver puts pressure on the accelerator, then the engine turns back on.
It is commonly applied to the phenomenon whereby an engine abruptly ceases operating and stops turning. It might be due to not getting enough air, energy, fuel, or electric spark, fuel starvation, a mechanical failure, or in response to a sudden increase in engine load.
3. Fuel System Problems. If you`ve ever run out of gas, you know from experience just how quickly a lack of fuel can cause your car to stall. An empty gas tank is certainly one way that your engine might fail to get fuel, especially if you have a gas leak that`s making you lose fuel faster than expected.
Malfunctioning spark plugs can make an engine stop for a while and resume its normal functioning. It can happen when you are driving. The engine can also sound rough when idle. The misfires affect the proper functioning of your car`s engine due to failing spark plugs that have no power to ignite the fuel-air mixture.
Some of the most common sensors that lead to engine stalling include the mass airflow sensor (MAF), engine coolant temperature sensor (ECT) and manifold absolute pressure sesnsor (MAP). The idle air control valve (IAC) and exhaust gas recirculation valve (EGR) are also well known for causing engine stalling.
Select first gear. Gently put pressure on the accelerator until revs reach around 1500. Slowly lift pressure from the clutch pedal until you find the biting point. When you are ready to release the handbrake, continue slowly lifting the clutch pedal and putting pressure on the accelerator.
So the auto-start-stop system can be used without any concerns in modern turbo engines, the manufacturers wouldn`t have put it in if there was any.
Faulty spark plugs can cause the car to exhibit starting troubles. Worn out plugs does not produce sufficient sparks, which is needed for starting the engine. This results in the engine to stall and fail to start quickly.
When the EGR valve is clogged or dirty, as they are prone to, it may not function properly causing the engine idle rough, stall at idle speeds, cause the car to get poor fuel mileage, or emit a strong smell of fuel due to excess hydrocarbons which also results in failing emissions tests.
Many modern vehicles are designed with several fail-safes to help protect the engine in adverse conditions. One of this is an automatic shutoff when the oil pressure drops to a certain level, or the oil level drops too low (note that this is not true for all cars). This causes the engine to stall and die.
With the fuel pressure gauge attached, start the engine and let it idle. Disconnect the vacuum hose from the pressure regulator; the pressure should drop approximately 8 to 10 PSI. If it does not, suspect a problem with the regulator or its` vacuum supply.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Truck stalls when shifting into drive from park or reverse
ANSWER : Hi there. The vehicle running great, once past the initial stall, leads me away from a fuel delivery concern. The stalling issue may be, the minimum airflow rate is not properly set. This could be the result of a dirty or worn throttle body. Cleaning and/or making an adjustment to the throttle body may correct the problem. Engine running at idle, plug the IAC passage, and the RPM (revolutions per minute) should be at or near 400 rpm. A vacuum leak present could also cause the engine idle to be improperly controlled and needs to be identified before any adjustments are made. I recommend having your vehicle’s stalling issue be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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Can front wheel drive car engine power rear wheel drive
ANSWER : Anything is possible with enough engineering. The changes you are looking at would take major structural changes and would definitely not be an easy job. You could possibly consult a manufacturing engineer to get more details on how this could actually be carried out and whether it would be feasible.

Read Full Q/A … : Stalls while driving

My car is briefly shutting off when driving and stalling out when stopped.
ANSWER : Hello. Stalling issues can arise from a variety of faults. Have any warning lights come on? You may want to have the vehicle scanned for codes anyway. Typically you turn to the fuel and spark first to make sure they are working correctly first. You can hook up an inline fuel gauge to make sure you are getting the proper amount of fuel to the engine. This needs to be placed after the fuel filter to test that as well. You can test the spark plug wires to make sure the plugs are receiving a strong enough signal. You may also want to pull the plugs and make sure they are not fouled and are gapped correctly. Several sensors may also be failing, but those should show up on a diagnostic scan. With an issue like this, start with the easiest components to test and work your way through the possibilities until you find the fault.

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Could this cause ur car to stall in warmer weather? My car never stalls during winter months. But from spring on its a neverendin
ANSWER : You should have the check engine light and engine scanned to see if the engine may be running lean due to low fuel pressures or clogged injectors. You should also have the mass airflow sensor cleaned and checked for proper readings and replace if not within specifications. The vehicle runs richer in colder weather and may be the reason for not stalling. You should clean injectors, clean throttle body and idle control valve then clean mass air sensor and relearn idle.

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After driving awhile, when idling, RPM drops below 500 & car stalls. Happens rarely but RPM fluctuates, and drops suddenly.
ANSWER : If you are having a stalling problem then you may have a computer code stored in memory. I suggest having the computer scanned to see if there is any codes stored and diagnose them as needed. The intake hose and air filter should be inspected for leaks in the hoses and dirty or leaking air filters. If the air filter is dirty or leaking then have the mass air sensor cleaned. If you still need help, have a mechanic diagnose the stalling issue for you and let you know exactly what repairs should be done.

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My vehicle stalls while driving and has trouble restarting – 1993 Jeep Wrangler
ANSWER : This problem may involve the heavy duty test tools, such as an oscilloscope, but it seems likely that the ignition control module has all but completely failed. It lives in/on the distributor – a hot place with a lot of vibration. Testing the spark path from trigger to spark plug is needed: from the magnetic pickup in the distributor to the ignition control module to the cap & rotor, plug wires, and then the plugs themselves.

I would recommend having a mobile, professional mechanic, such as one from YourMechanic, perform an inspection to determine why the car is starting and dying and give an accurate assessment of the damage and cost estimate for repairs.

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Car stalls out while driving.. Power gone..battery drained.. dashboard goes crazy.. Told alt..or ignition stuff.won’t start…
ANSWER : The alternator is likely, but this would completely drain the battery and if done too many times can render the battery useless. The situation must be diagnosed properly by an experienced mechanic to find the solution. Electrical components like the ignition switch or an engine speed sensor can also cause the vehicle to stall. but do not usually drain the battery. I’d suggest having one of our mobile experts pay a visit and assess the concern with your battery.

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Why the car stalls when put on Drive?
ANSWER : This may be a sign of a faulty MAP sensor as the vehicle responds adversely to a load put on the motor (i.e. putting it in gear) as you describe. The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the [MAP sensor]((https://www.yourmechanic.com/services/manifold-absolute-pressure-sensor-map-sensor-replacement), it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak.

Blue smoke coming from your exhaust generally means that the motor is burning the engine oil. This can happen for a couple of different reasons such as worn piston rings or leaking valve guide seals. When this happens, the engine oil is burned in the combustion chamber along with the fuel which is what generates the blue smoke coming from the exhaust.

I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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