Driving home from my holiday my 1997 Acura Integra’s Check Engine light came on. The car was also having trouble in fifth gear and on hills. I put some fuel injector cleaner and octane booster in and the engine ran smoothly the rest of the way home, but the light never went out.
What is it I should have checked for?
(Yeah, I’m going to a mechanic eventually.)
Nothing you can check w/o a code reader. A steady check engine light means the engine management detected a fault that can cause the cars emissions to exceed specification. That’s it.
It means to check the fill level and condition of all fluids, to check for obvious leaks, out-of-spec gauge readings, unusual sounds or loose/missing belts. If all seems normal, you or your mechanic can use a scan tool to extract stored trouble codes from the computer.
Mine comes on every 5000 miles as a reminder to get an oil change. The staff at the oil changing place reset it when they are done. I always worry that it is something more serious, but so far, it isn’t.
On mine, that is a different light. After 203K I’m not sure that light will ever come back on… 
My check engine light came on last month for the first time in the 94,000+ miles that I’ve had my car. Took it to the mechanic. He read the on board computer which said that there was a vacuum leak. Mechanic changed an old, crumbling hose and it was good to go.
oh. Ok. that’s not it.
Carry on!
Usually Autozone or Advanced Auto Parts will check the light for free and reset it for you. If may be something easily diagnosed (spark plug, o2 sensor) or it may be something that could be 3 or 4 different parts and require you to take it to a mechanic, depending on your knowledge level.
OR, you could disconnect the black terminal on your battery for 30 seconds. Restart your car and see if the light goes off. If it does, it could have been a temporary condition. Take note of when it comes back on to help you diagnose the issue.
Thanks jtgain, I didn’t know any of that. Actually, I think my buddy has a device that can check the computer - depending on how generic such devices are. (He has one, but for an American car.) I’m thinking it may be as simple as an o2 sensor or maybe a pcv valve.
But I never liked working on cars and so I will take it to a mechanic.
But first, I think I’ll disconnect the battery. That one is so simple it is well worth the effort.
If it *is *a spark plug I’ll definitely take it to the mechanic - I’m not sure the plugs have *ever *been replaced and I suspect at this point they are fused to the wiring harness and you’d have to replace it all.
It also may be a signal to replace the car. It burns oil terribly and after 203K, it doesn’t really owe me anything.
203,000 miles on the original spark plugs? please tell me you’re joking.
Nope. Although I can’t be sure, because my memory is pretty poor, but it certainly has been many many miles on these. It gets 30 miles per gallon when I drive gently and has always run well, so I let it alone.
It also had 187K on it when I replaced the clutch for the first time.
I’m certainly no mechanic, but I have read that the most common cause of a “check engine” light coming on is simply a loose gas cap and that if this is the cause, simply tightening it will solve the problem.
Here’s how you can get the code on a 97 Integra without having to take it to a mechanic or parts store.
That’s probably true about it being the most common cause. I know it’s happened to me a dozen times and I’ve never had a light for anything else. Luckily, in my vehicle, I can flick the switch on and off 3 times and get the code and I know the evap leak codes that point to the gas cap. It usually takes a couple of days driving around after tightening the cap for the light to go off because the computer only checks every X miles or X engine starts, so although you solve it, you won’t know for a while.
To expand on this, on my car, a 1996 Ford Contour, it can mean excessive pressure from gasoline vapors in the tank. To remedy this, I need to loosen the gas cap to vent pressure, then tighten it back up. I then need to run the engine through three cycles of normal driving, allowing the engine to get warm, then allowing it to cool before starting again. On the fourth startup, the engine light should go out. If it doesn’t go out, then that means it’s something else, in which case you might want to take your car to an auto parts store. Many will diagnose a check engine light free of charge and tell you what it indicates. You then might want to take it to a mechanic if it indicates the problem is something you can’t fix yourself.
Last year, I had the check engine light come on and took it to the parts store. They determined it was from a cylinder misfire. However, since my car was running normally, they reset the computer and the light went out and hasn’t come on since. I was even able to pass my state’s emissions check without a problem.
Is the gas-cap-thing some thing that commonly come on as a car gets old? I mean, I’ve seen the check-engine light once in all the 203K miles I’ve driven.
modern cars have to have the fuel system sealed. vapors from the gas tank have to stay in the system until the engine is started, at which point the engine draws them off and burns them. if the gas cap isn’t tightened properly, it can cause an evaporative emissions fault. I suppose if the car’s old, the gasket on the gas cap can be torn or otherwise broken down.
My car wasn’t that old when this happened. It was only two or three years old then. And it is a known occurrence to Ford. The owner’s manual gives it as one of the causes of a check engine light and says to eliminate the gas vapor buildup first as that is the most common cause of the check engine light coming on on that particular model. It has rarely happened more than twice in the life of my car and I still have the original gas cap on it.
In California, at least, Autozone not longer does this.
Reasonable thing to do.
Why? To turn off the light temporarily? What purpose does that serve?
If the trouble code memory is cleared by resetting it or by disconnecting the battery, the evidence is gone until the light comes on again. If you’re going to take it to a mechanic to have the problem fixed, don’t futz with anything beforehand or you’ll likely make his job harder and more expensive.
Once the battery is disconnected, you step on the breaks or turn on the lights to drain the last bit of power, thus resetting the CEL