Check engine when i am driving the check engine always flashes on the dashboard what would be its possible cause

If it is the check engine light, Yellow light that looks like a engine, or may say "Check engine", Yes, it is safe to drive until you can get it checked. As long as the vehicle is driving normal. If the light starts flashing, DO NOT DRIVE it. A flashing check engine light means a misfire and could cause a fire due to raw fuel going down the exhaust into the cat converters.

Have the check engine light scanned for codes related to this problem first. You may have a charging system issue causing low voltage resulting in the lights flashing/stalling.

Check this about the four most common Check Engine Light scenarios and what to do:
* The Check Engine Light turns on and off or flickers.
If the Check Engine Light comes on in the city but goes off on the freeway, then the fault is present during city driving conditions. Pay attention to whether or not the vehicle runs or drives any differently when the Check Engine Light illuminates. If vehicle performance does change, drive the car as little as possible and take it to be checked by a service professional as soon as possible. If there is no change in vehicle performance, you can drive home, but have it inspected as soon as possible. In this condition, you run a risk of the vehicle dying or not starting.

* The Check Engine Light comes on and stays on.
If the Check Engine Light illuminates constantly during driving with no noticeable driving or performance problems, there is a permanent fault in the emission control system. When this happens, the computer that controls the emission system usually has a backup program that runs while the fault is present. (These backup programs are often referred to as "limp home" mode programs.) You should get the vehicle serviced as soon as possible, but in most cases, the vehicle will continue to operate, though you run a risk of it dying or not starting.

* The Check Engine Light illuminates, stays on, and there are performance problems.
This means that a vital component of your emission control and engine management system has a serious problem. It usually involves a component or system needed for the vehicle to run at all. In most cases, drive the vehicle as little as possible. In many cases, the vehicle is not safe to drive at all -it could stop or stall out at any moment. It is best to pull over to a safe place and have the vehicle towed to an automotive diagnostician for a thorough inspection and repair.

* The Check Engine Light light comes on and blinks in a steady pattern while driving.
Don't confuse this steady pulsing of the Check Engine Light light (usually one or more flashes per second) with a flicker (see above). The Check Engine Light may stay on steadily or it may flash when the vehicle is accelerated. This is very serious. There is a severe failure of the emission control system that is causing the engine to misfire to the point that the catalytic converter is damaged each time the Check Engine Light flashes. It may mean that the catalytic converter is overheating to the point that it will glow red or, in extreme cases, start a fire on the underside of the vehicle. Immediately pull over to a safe place and have your vehicle towed to an automotive diagnostician for repair. Vehicles can be severely damaged and even destroyed by fire if this condition is ignored for too long.

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The truck is telling you that there is a problem with the 4x4 system and the 4x4 should not be available for use. the system is extensive so it can be anything from a wheel speed sensor to a transfer case ring gear. the good news is that if its not a check engine light it shouldn't cause a brake down. i would find a good auto shop and have them use whats called a modis scan tool and find out why the light is on.

The information below was complied by me, it explains what causes the check engine light to come on and the process of finding the cause.

When the Check Engine/Service Engine Soon light (Varies by make) is turned on the computer control unit (called the PCM) has sensed a fault in the electronic controls of the engine and/or the emission system. When this happens you will seldom feel the car engine run any different. There are about 200 possible faults that turn the Check Engine light on, to know what has developed a problem you must have the system tested, this is called an OBD2 fault code test, Kragen and Autozone parts stores do this testing for free.

DO NOT DRIVE IT.....Driving it when the check engine is flashing may cause a simple problem to become a major problem if not fixed right away. Cruise control will always disable when the check engine light is on, when cleared, it will work again. Blinking light means serious malfunction, needs to be repaired right away. This can be many things, from simple multiple cylinder misfire, to something more serious.

the flashing light means is a severe issue that could cause catalytic converter damage, probally a bad coil known for it in the 4.6l and 5.4l, need to scan computer and retreive code to ***

Had the same problem with check engine light coming on, loss of power, missing always starting to accel and in speeds between 10-30 mph, little smoke coming out of exhaust. Took it to the shop come to find out the catylic converter had been rusted out due to wear and tear or age. Spent 200.00 dollars since I knew the guy to replace it and now the car runs great.

thats the heater coil symbol for the diesel engines.
does it stay solid at beginning as normal?
if the car drives normal, then maybe its just a loose connection/wire somewhere

any time the check engine light flash on and off you are causing damage to the cat.