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Engine light blinking then goes off

I was driving around 70-75 mph when my check engine light came on and started flashing rhythmically. It went off about a minute, then a minute later it came on again. After another minute it went off. I haven’t had it happen since then. Is this something serious? I have 2001 Chevy Blazer, and I recently replaced my thermostat because the engine light was on about a month ago.

The CEL flashing will have stored trouble codes in your computer…You can have the codes read and then you will know why the light came on…

…and yes, it is serious. If it starts blinking stop driving. You could have a small problem that will turn into a big one. Blinking is bad. It usually indicates a fairly bad engine misfire. So next time, safely pull over. If it won’t stop blinking you’ll probably save more in the long run with a tow. If it does stop blinking, drive it gently to your mechanic.

Big box auto parts stores like Advance and Autozone will read the error codes for free. if you do this write down the exact code(s) - such as P1234

If check engine light blinks that means its serious and you should pull over immediately. Thermostat doesn’t throw a code so I’m not sure why you change it

CEL on means there is a problem that you need to check on this week. Light flashing, means you should pull over to the side of the road and get your cell phone out.

 That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

Actually, the thermostat DOES throw a code.

If it’s serious, why did it turn off and why hasn’t it been on at all today?

No - the thermostat can’t throw a code. You probably had a code something like P0125 or P0126 which refers to the coolant temp not being high enough for this or that. A common cause would be a stuck open thermostat but its not the only possibility.

If you presume to know so much why do you need to ask up here?

Because s!@# happens - haven’t you ever had an intermittent problem with anything? The last time I had this happening to me the light started blinking and before I got off the road a valve seat had dropped out of the cylinder head and destroyed the engine.

Look - how the heck are we supposed to know exactly what is going on? You gave almost no info about your vehicle. You didn’t even tell us how many miles are on it let alone anything about its maintenance history.

A blinking engine light is a serious problem. It sounds like you just wanted everyone to say “oh, its ok - just a ploy by Chevy to get you to the dealer” - well its not. But if you’re happier thinking that drive on and get ready to foot a big bill.

Well, I guess I should say it threw a PO126 because it failed in the open position and had to be replaced.

I guess since you refuse to tell year, mileage, engine size or code, I’m gonna haveta assume it’s later than a 1996 model Which is what is known as OBD2. When check engine light flashes it basically means that a misfire is happening that is bad enough to cause severe damage to the catalytic converter. Tune up expensive? Keep driving and add the price of a cat to that!

Dude, chill.

No one asked for my mileage or maintenance history. had they asked, I would have responded. I understand that it’s serious, but if it’s serious why did it turn off? That’s what I was asking about, not that I didn’t believe you.

You might want to take questions at face value and not be rude and bitchy. I will be checking the code today if possible.

I did give the year in my original post. People didn’t ask mileage. It has 96,000 miles on it.

Serious problems come and go, like heart attacks. You shouldn’t ignore it, because it will probably come back.
In the future, if you don’t like all of the free advice on this board, consult your owner’s manual. It does cover the situation of the check engine light flashing.