when your check engine light keeps turning on and off, what is most likely causing it?

Question

i drive a 04 mustang gt and just recently my check engine light keeps turning off and on and my car drives great

Answer 1

get a code scanner to know for sure, but usually it's a oxygen sensor, one of 4

Answer 2

If the check engine light comes on right when you start the car or anytime before the engine is warm, take it to a garage of your choice and tell them to scan the car, that will bring up any trouble codes that are stored.
IF it only comes on when the engine is warm, then it could be the egr port, to solve this, remove the plastic part of the intake that goes into the throttle body. Next remove the throttle body, you will see a 3"+ hole, you should also see a channel that runs a semi-circle at the back of the intake manifold, right beside the 3"+ hole, 9 times out of 10, it will be filled with black soot, carbon, w/e stuff a rag in the big hole so nothing gets in, take a small pick or even coat hanger, clean all the gunk out, vacuum it up, install tb, plastic intake and any wires you had to remove to get access. Typical 4.6 problem, just did mine last week, and haven't seen the light since. Hope this helps

Answer 3

A 'Check Engine Light' that comes on and off is detecting an intermittent problem with a sensor.Bring the vehicle to an Auto Zone parts store and they will check it out for free.They can tell you what code or codes are being displayed and then you can decide as to how you will make any repairs from there.Sometimes it could be simple as a loose connection (check all harness connections under hood) or something beginning to go bad.You can also disconnect the ground cable for a short time and replace to see if the light goes out and stays out as this is just an intermittent problem.It may even be detecting an emissions problem.If the light does the same after doing this.Get it checked out as soon as possible.No need to worry.

Answer 4

Unfortunately, in most newer cars, the Check Engine light is just a general notification that something's wrong, without being specific. It takes a mechanic with a computer gizmo to read the circumstances that caused the light to come on. As the previous answerer mentioned, you can check the obvious things, like fluid levels, etc, but if it's something beyond that, then it'll have to be determined by the mechanic. Hope you find it though.

Answer 5

The check engine light comes on when something in the engine needs attention. At the point where it's flickering or turning on and off, whatever it is that needs attention is almost at the critical point. Probably, then is going to be a fluid level...when the car moves, the fluid moves one way, and the light goes off, and when you brake, the fluid moves another way, and the light comes on. (That sort of thing.) I'd check your oil, transmission fluid, brake fluid, coolant, and windshield wiper fluid.

Answer 6

Your sensors could be dirty. Do this and see if it goes off.. take the turminals off the battery, wait 5 mins. Garenteed to turn that off! But, it will needless to say come back on. I have a Tempo 1994, after a year of driving it that light kicked on. I asked my dad about it and he told me to do that. The secret... It is made to do that so you take it to the dealership to get it tuned up or find the problem, and they get paid. It is all in the brain of the car. Programed. As long as that car runs, their is nothing wrong with it. it is 2007 and my Tempo is right outside ready to run like it always had, ps. The light still kicks on. :-) Hope this helps.

Answer 7

By turning off and on are you saying flashing? If the light is flashing get it checked out by someone with a reader, either a dealer, or auto zone. The Stang thinks it's important, you should at least get it checked. (SOON)

Answer 8

it rather is a probability that when the gas point drops under a particular factor that there might perhaps be air being drawn into the gas equipment. if it is the case, the gas injector code(s) and the oxygen sensor code(s) might desire to develop. If the codes point out a lean gas blend, it is definitely possibly. previous that, with out actual palms-on, we are all only guessing.

Answer 9

take your car to autozone the next time it comes on.leave the car running when you go in so it dosent reset while your waiting for them to come out and test the trouble codes that its bringing up.

Answer 10

Oil level may be down check it urgently before driving.