Truck wont start gives check engine light ran fine yesterday

What makes 2008 silverado truck all of sudden show check engine and won't start

My car has 39000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi there. The Check Engine Light is a warning system that illuminates when an OBD-II error code is triggered. There are literally hundreds of possible reasons why the Check Engine will light up. In most cases, this is caused by a sensor that has failed, an idle control valve or ignition control module that has broken. In order to determine the exact source of your engine starting troubles on your Silverado, you might want to contact one of our mechanics who can complete a Check Engine Light inspection which will permit them to download those OBD-II error codes and pinpoint the source of your troubles.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Check the battery if there is a slow crank and a clicking sound, and the car engine won`t start. However, if the check engine light illuminates, the issue could be the engine or fuel pump. If your vehicle doesn`t start, call AAA, roadside service, or another towing company to take your car to get it repaired.
The issues your Chevy Silverado may face that cause the check engine light to turn on include: FAULTY OXYGEN SENSOR. LOOSE GAS CAP. FAULTY CATALYTIC CONVERTER.
Connected to the battery is the alternator, which works to generate power for your vehicle`s electrical components. When you have a brand-new battery but still can`t start the car, the alternator might be the issue. Cold and damp climates may increase wear on an alternator, causing it to fail.
When your check engine light begins flashing, it is most often caused by a charging system misfire. The fuel, oxygen, and spark in your vehicle must operate in a specific order to power it properly. Unfortunately, if one of these three cylinders malfunctions, the entire system will suffer.
Some other typical reasons engines fail to start include:

Low or discharged battery. Corroded or loose battery cables. Starter motor relay failure. Ignition switch failure.

Dead car battery: A dead battery is the most common reason why a car won`t start. If you have a battery tester, check your battery to see if it`s weak. If you don`t have one, try to jump start your car with jumper cables.
A loose gas cap is one of the most common reasons for the check engine light to go on. Check that your gas cap is screwed on securely and that it`s in good condition. If you have a tank of bad gas in the car, your check engine light may come on.
Other mainly common reasons for a Check Engine Light are faulty head gasket, dirty mass airflow sensor, a malfunction with the fuel injection system, faulty emissions control part, broken oxygen sensor, or damaged spark plugs to name a few.
The battery can be fully charged but still not be able to start the vehicle if it is failing or has a dead cell. Other likely issues are the fuel pump, ignition switch, battery cables, starter, or a clogged fuel filter.
When your engine cranks but won`t start or run, it could mean your engine is having trouble producing a spark, getting fuel, or creating compression. The most common causes are problems in the ignition (for example, a bad ignition coil) or fuel system (for example, a clogged fuel filter).
A solid check engine light indicates a problem that needs to be addressed but is typically not urgent. A flashing check engine light indicates a severe problem that requires immediate attention to avoid further damage.
Misfires don`t simply go away – they need to be addressed immediately. Even if they don`t get worse, they certainly won`t get any better unless you take the car to a mechanic.
The crankshaft position sensor monitors the position and speed of the crankshaft and other parameters that play an important role when starting the engine. If the crankshaft position sensor is having a problem, the vehicle may have intermittent starting issues or not start at all.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
Check your gas cap first. Many vehicles have a loose gas cap indicator that will be triggered before your check engine light comes on. If your gas cap is loose or the seal is not tight, the vapor leakage can cause your fuel system to trigger the check engine light.
These problems can range from faults within the electrical system, the engine, fluid levels or to problems within the car`s emissions system. The problem can even be as simple as forgetting to tighten your gas cap – in fact, this is the most common reason why check engine lights appear in the first place.
What concerns can a loose gas cap cause, well a check engine light? A loose gas cap will not only let in dirt and grime, but it can also allow fuel vapors to escape. These vapors can trigger an error in the emissions system, which would light up the check engine light.
Press the odometer`s Trip and Reset buttons while turning the ignition key ON. After turning the key ON, release the odometer Reset and Trip buttons to check if the Diagnostic Trouble Code or DTC appears on the odometer display.
If you`re unable to start your vehicle, check and see if the headlights and dash lights come on. If they shine bright and clear, that means that the battery and alternator are likely not the cause of the problem. If they were, there wouldn`t be enough power to run the lights.
One common reason why a car won`t jump start is because the battery is completely dead. If the battery is completely dead, it won`t have enough power to turn over the engine, even with a jump start. In this case, you`ll need to replace the battery to get your car running again.
If the alternator`s fuse or fusible link is blown, the alternator will not be able to charge the battery. The battery then doesn`t store enough power for starting the car or keeping it running.
A Blinking Light is Bad

In most cases, a check engine light will shine steadily, a serious reminder that something is amiss in your vehicle. If the light is blinking, however, your minor annoyance and concern just got elevated. If the check engine light is blinking, get to the nearest trustworthy mechanic you know.

A check engine light flashing– as opposed to a continuously illuminated check engine light – should never be ignored. A flashing CEL indicates a severe problem, one that requires immediate car repair. In other words, if your check engine light is flashing, pull over and call a tow service.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?
ANSWER : Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the wires to the oil pressure sensor and make sure that they are connected and not broken. If everything looks good, then the oil pressure sensor may have failed. Plus, check the computer for codes and see what is stored. This will lead you to the part that could have failed. I recommend replacing the oil pressure sensor then checking to see if the lights will go out. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with the warning lights that came on.

Check Engine Light comes on after starting pickup
ANSWER : Hello there, thank you for asking about your 1992 Isuzu Pickup. A professional will have the correct equipment to read OBD1 codes. Retrieving the diagnostic trouble code(s) is the first place to start when diagnosing your vehicle. Increasing RPMs changes engine load, which can in turn affect many different sensors and components, causing the Check Engine Light to illuminate. The only way to narrow down the options and find the culprit is through in person diagnosis with an OEM compatible scan tool. A certified technician from YourMechanic can retrieve the OBD codes at your home or office.

While driving on freeway truck goes into a limp mode, and the check engine light, abs light, parking break light, service brake
ANSWER : It is possible that you could be having an issue with your powertrain control module. This is somewhat of a common problem on many GM vehicles. I would recommend having your vehicle inspected by the dealership to determine if the powertrain control module is functioning properly. If not, a reflash of the powertrain control module may resolve the issue but often times it must be replaced.

Car wont start–check engine, oil pressure, and battery light all on
ANSWER : Hi There,
If your oil pressure falls below a specific level, the ECM (car’s computer) will automatically shut the engine down to avoid further damage to the engine. This is done as a safety precaution. Typically, the oil pressure light will come on when you are in fact low on oil, the oil pump is not pumping oil properly or in some cases when the oil pressure sensor is faulty providing a false reading. In any case, this should be looked at as soon as possible by a qualified mechanic. I would suggest having one of our experts here at YourMechanic come to your location to take a look at your vehicle.

Check engine light comes on and engine stalls but starts right back up. Upon restart the check engine light is off with no problems.
ANSWER : Hi there. It seems that there could be a loose wire or loose ground to the transmission sensors. First you will need to get a scanner and scan for any codes that are pending or stored in the ECM (computer). This will give you a location to start that is causing the engine to stall out. If you get the code P1684, then check the battery cables to see if they are loose or corroded. The code P1684 means that there has been a loss of electrical power to the ECM (power). If you need further assistance with your vehicle stalling intermittent, then seek out a professional, such as one from Your Mechanic, to help you.

Fuel pump engages. Batery good, alternator good volts, jump start helps when wont start. Temp does not matter. Intermittent?
ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

I parked my truck for 5-10 mins. Tried to turn it on, now it wont start, called a tow tow truck 15-20mins later my truck turned on
ANSWER : It is very likely that you have a powertrain control module failure. This can happen often on many GM vehicles. I would recommend having the powertrain control module tested and replaced as necessary in order to resolve this issue. After the powertrain control module is replaced, a reflash procedure will be required so that the vehicle can relearn all of its primary engine data. Once the reflash is completed, your vehicle should no longer have this issue.