Cranking when starting car
My Mercedes started having a slight problem starting. It never did this before. Last week when I started my car it cranked for a few seconds. The day before I had been driving long enough for the engine to get pretty warm. Then after the engine cooled down for a few of hours I had the cranking problem. Do you know what’s causing this? Any ideas
Experienced mechanics share their insights in answering this question :
Hello. There are a few things that could be going wrong here. The battery could have low voltage at times, causing the car to be hard to start. There could also be an intermittent problem with the starter, causing a problem with starting the car.
If the camshaft sensor and/or crankshaft sensor has an intermittent problem, this could also cause a cranking problem making it difficult to start the car. The camshaft and crankshaft sensors read engine timing and if they are not working properly, the car may not start or will be difficult to start.
I would recommend that you have the electrical system inspected, by a certified technician, like one from YourMechanic. This technician will also be able to inspect the camshaft sensor and crankshaft sensor to make sure they are working properly.
How to Identify and Fix Common car Problems ?
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Check Crankshaft position sensor – Crank No Start
When the motor crank position sensors fail, you will see the following symptom: The Mercedes-Benz engine is turning but won`t start because of the failure of its crank position sensor. Replacing the crank position sensor is simple and fairly inexpensive.
The reason for your car taking longer to start can depend on a variety of conditions including weather, battery health, starter health, fuel pump health, and other factors.
The most common reasons a Mercedes-Benz CLK500 won`t start are a dead battery, an alternator problem, or failed starter.
Bad starter motor: If you hear a single click when you turn the key, but the engine won`t start, that could mean there`s a problem with the electrical system. The starter motor is responsible for physically turning the engine over and getting the engine to fire. If this is the issue, you`ll need a new one installed.
When an engine cranks for a long time before it starts, either spark or fuel is missing or weak and each has its own reasons. Most of the time, the air / fuel mixture has been disturbed and there is too much air or not enough fuel.
Bad Sensors
One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft. The computer uses the information from this sensor to know when to fire the spark plugs. If the sensor isn`t working, the spark plugs won`t fire, keeping the engine from starting.
The most common reasons a Mercedes-Benz ML500 won`t start are a dead battery, an alternator problem, or failed starter.
These are: Your key fob battery is low or empty. This prevents the Electronic Ignition System (EIS) from functioning. The Driver Authorization System (DAS) is not functioning, and thus failing to verify the key properly when inserted into the ignition.
Find the reset button on the left side of your instrument cluster. Press the reset button and hold it until your display shows “To reset: Press reset button for 3 seconds.” Push the reset button again and hold it in until the display shows the system has been reset.
Slow cranking could be the result of several possible conditions, and as you`ve suggested, the fault might reappear or worsen. Possible causes are a degraded or defective battery, faulty electrical connection, a charging system problem, a bad starter or battery rundown when parked.
If your Mercedes is experiencing starting problems, then there could be an issue with the combustion process, originating likely from the fuel system, particularly the fuel pump. Occasionally over time fuel pumps can become clogged with residue and buildup.
Slow cranking could be the result of several possible conditions, and as you`ve suggested, the fault might reappear or worsen. Possible causes are a degraded or defective battery, faulty electrical connection, a charging system problem, a bad starter or battery rundown when parked.
If the engine cranks slowly but doesn`t turn over, your Mercedes probably has a battery issue. When battery power is low or there is corrosion on the terminals, it will negatively affect your power output, and you`ll struggle to start your Mercedes.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
When I go to crank my car the key stays in the start position and the car is constantly trying to crank itself.
ANSWER : First, let’s make sure about some terminology before I proceed. I will assume the motor is actually turning over. If the car is trying to start, the motor has to be turning over or it is not trying to start. This is an important distinction when diagnosing the starting system. As a technician, I go to different parts of the system based on this description.
If the key is stuck in the start position, this is a ignition lock cylinder issue and the reason the starter continues to turn the motor over. If the starter is turning but the motor is not, then the starter is likely the problem. Either that or the teeth on the flex plate are all gone. This would require removing the transmission to repair.
If the car runs intermittently, this can be a big challenge. And it also means the starting system is working. It will need to be diagnosed when it is failing. A working car cannot be diagnosed because there is nothing wrong. Where you park your car should not have any affect. It certainly could be a wiring problem. Wiring problems hide really well and can happen anywhere in the miles of wires that are in your car. Isolating the system that is failing is really important here. At the moment I am unsure which system is failing. Starter system, ignition lock cylinder and or ignition switch electrical or something with the engine control system.
When the car is failing, you need to check for spark and fuel pressure. If neither is present, this is a clue. Usually the crank sensor will do this. Does your car have a tachometer? If so, does it move at all when cranking. This is a clue whether or not the cam and or crank sensor is working. Is there a Check Engine Light on with the key on? If there is a Check Engine Light, the code or codes can be used for specific diagnosis.
All of these concerns will send you down a diagnostic path. Be sure not to confuse yourself by misinterpreting multiple system failures. If the key does stick in the start position, this would be the first problem to solve. After that, does the motor actually turn when the starter turns? After that, the question of "Why won’t it start?" is first answered by finding what the motor is lacking. Fuel, spark etc… Good luck.
If you need assistance with these checks, contact a certified mechanic who has the tools and experience needed to properly diagnose this starting issue with your car.
Map sensor car won’t start up good ?
ANSWER : Your MAP sensor is an important input for your computer. It helps determine the load on the engine to calculate the correct amount of fuel to inject. It sometimes takes a few seconds for the vehicle to realize that the sensor is not producing a good signal.
At that point, it will use other methods to determine the fuel rate, such as pre-programmed fuel maps, throttle position, etc. I would suggest replacing the MAP sensor and retesting. If you would like to have it checked first, a certified technician from YourMechanic will be able to scan your vehicle and test components to determine the root cause of your starting issue before making a repair.
Car won’t crank when it’s cold and now won’t start at all
ANSWER : Hi there:
Usually this issue is cased by low cranking amps inside the battery. If you’ve recently had the battery replaced, it’s possible that an electrical component that makes up the charging system might be damaged or faulty. It’s also quite possible that the main electrical relay or the starter relay is giving you fits. To know for certain what the exact issue might be on your 1989 Toyota Camry, you should have a professional mobile mechanic complete a car is hard to start inspection, so they can pinpoint the source of your issues and recommend the right repairs.
My car starts fine but always like once a month it doesn’t start it cranks ok but it will not start if I let it sit for 6 hours
ANSWER : Hi There,
What you are describing sounds like an ignition coil that may be failing. Ignition coils are prone to this type of erratic functioning or heat cycling when they are beginning to fail due to the temperature fluctuations under the hood which ultimately cause them to shut down causing the car to only run after cooling down for 30-40 minutes. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings and decrease or eliminate the coil’s ability to function. This process will repeat itself continuously until the coil ultimately fails completely and must be replaced. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your ignition system.
The car crank but won’t start
ANSWER : Hi there. This does sound like an issue with the wiring. If the check engine light is coming on every now and then this means that when it does not come on there is no power to the computer. This can be the wiring harness issue or an ignition switch problem. I would have to test for voltage to the computer when the problem is occurring to be able to find where the issue lies. If you need assistance, a certified YourMechanic technician can be dispatched to your location to inspect your vehicle’s non-start issue and suggest any necessary repairs.
car hesitates when trying to start the car ,but when started then i shut car off and start again it will start right up
ANSWER : Hi there:
Sometimes when you have problems starting an engine initially it is caused by a restriction in fuel flow; caused either by clogged fuel injectors or the throttle body that needs to be cleaned. Once the fuel starts to flow and engine warms up, it’s much easier to start. However, it could also be an air filter, EGR valve or other components that causes this issue as well, which is why it’s best to have a professional mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of this issue.
The car is having trouble starting up ,70 percent of the time it starts right up. the other 30 percent, it randomly won’t start its
ANSWER : Hey there thanks for writing in about your 1998 Honda Accord. This could be a few things. A faulty ignition switch, a failing crank sensor, or possibly other faulty sensors could be the cause. To have this taken care of, consider having a certified technician, such as one from YourMechanic, come to your car’s location to diagnose and repair the hard start issue.
