Check engine vs. Service engine

[snopes]

omment: Hi, I was wondering if you have ever heard the story about why
the "Check Engine" light that comes on on your cars dashboard was changed
to "Service Engine Soon" I was told the story of two old ladies were
driving one day, the "Check Engine" light came on so they stopped, popped
the hood to "Check" the engine and were subsequently hit and killed by a
car on the highway. Supposedly this prompted the big auto makers to
change it to "Service Engine Soon" after being sued by the surviving
families.

[diddy]

I would think that it was because "check engine" would be too confusing. People would look at the engine, not see anything visually wrong with it (not being qualified to tell the difference) and moving on and doing nothing until the car was unable to function. No lawsuit required (why must all these rumors have a lawsuit behind it??). The words "check engine" is very nebulous. I still see it though.

[Not_Done_Living]

How long ago was this change made? My car (2005) has a check engine light, as does my mothers 2008 vehicle. Of course they are both GM vehicles...

wouldn't this be a matter of semantics?

[queen of the caramels]

My 1998 Madza has a 'check engine' light as does Dh's 2003 Ford.

Though it's more of major/minor problem alert, certainly nothing to kill the car in the short term.

[Ana Ng]

My Beetle has a "check engine" light that I believe actually means "vehicle is on." It's never been off since I picked it up from the dealership eighteen months ago.

[snopes]

Originally Posted by Ana Ng

My Beetle has a "check engine" light that I believe actually means "vehicle is on."

Yeah, they're pretty useless as indicators of anything that actually needs servicing. On the last few cars I've owned the "check engine" light seemingly went on and off randomly -- the one time I took a car to a dealership to have the reason why the light was on checked, they said it was a software error.

[WildaBeast]

I think it's just a difference between different auto manufacturers. "Service Engine Soon" seems like it a GM thing from my experience -- the 1988 Buick I had in high school and the Saturn I currently drive both use that phrasing. If I remember correctly Honda uses no words at all but just an engine shaped icon. It seems like if been in other cars that used a combination of the two, like the word "check" over a picture of an engine.

[Roadie]

My check engine light has been on pretty much steadily for the last 2 years. It is on more than it is off. I finally took it in a few months ago after it stayed on steady for 2 months. The mechanic said there were 3 reasons it was on - none of which affects the drive ability of the car. One of which would cost more than $300 to repair. He said if it starts flashing, I should come back and see him.

I had a car with an 'engine' light that served as a warning to pull over, check if anything was wrong with the engine that I could see, then take it to a shop if I couldn't find anything wrong (it's usually a sensor or something like that, you can test it yourself in some cars by shorting out pins under the dash and what not). I can't see people having a problem with the difference between a 'service engine soon', a 'check engine' or a 'salad with chips' light coming on if people would RTFM.

[Johnny Slick]

And besides, who wants to "service" their car? Wocka wocka!

[Eddylizard]

The engine shaped light on my previous 2004 Corsa and my 2009 Tigra means the emission system is malfunctioning. The indication that I should get it serviced is when the trip meter display is replaced by "InSp".

Due to the shoddy nature of the LED display, I've only just worked out that it's InSp (presumably short for inspect or inspection) and not lnSp which is what it looks like - I spent ages trying to work out what LNSP could possibly stand for.

[TatorKate]

The only time I have ever encountered a "check engine" light ended in financial disaster. Once upon a time (the time was actually 3AM), in a land free of cell phones, I looked down to see a tiny illuminated icon. By the time I had figured out what it said, the engine had died. I took the walk of shame to a pay phone. After a humiliating phone call, a morning tow, and a mechanic's visit, I was informed that my timing belt had broken. I don't know which was more shocking-the $1000 bill or the realization that there is a car part called a timing belt. For those of you with a timing chain- don't rub it in. Suffice it to say, I am now terrified of the "check engine" light/icon/whatever.

Originally Posted by Ana Ng

My Beetle has a "check engine" light that I believe actually means "vehicle is on." It's never been off since I picked it up from the dealership eighteen months ago.

Oh and Ana- it too was a Volkswagen!

[RichardM]

Snopes, Ana Ng, and others:

The "Check Engine Light" and the variations thereof, could mean: "You engine is overheating and about to blow up." Or "The alternator has quit and the car is about to quit completely while you are trying to drive 65 on the freeway with 2 billion people about to run over you." Or "The gas cap is loose. Please close it fully."

The dealer and most independent repair shops are willing to read the computer output and tell you what the light means, often at no cost.

[BoKu]

It's worth noting that many cars have both Check Engine and Service lights. The Volvo 740 with Bosch LH-Jetronic EFI is a good example. The Check Engine light only comes on when something is amiss, but the Service light comes on at regular intervals to remind you to get oil changes and to unplug the EGR valve.

Originally Posted by RichardM

Snopes, Ana Ng, and others:

The "Check Engine Light" and the variations thereof, could mean: "You engine is overheating and about to blow up." Or "The alternator has quit and the car is about to quit completely while you are trying to drive 65 on the freeway with 2 billion people about to run over you." Or "The gas cap is loose. Please close it fully."...

Yup. If the Check Engine light is on but the car runs and behaves normally, it probably means that an emissions system has failed and the car won't pass smog. Sometimes it means that a critical system has partially failed, but the ECU is working around the problem. On a modern car it's pretty amazing how many sensors you can kill and still have it run.

If the Check Engine light is on, and the car is behaving abnormally, it's often something that the ECU can't work around and it has reverted to a "limp home" mode that offers enough power and drivability to get you home or to a repair shop.

Originally Posted by RichardM

The dealer and most independent repair shops are willing to read the computer output and tell you what the light means, often at no cost.

On many cars you don't even need a computer or code reader, you can coax the ECU to display the OBD codes directly. On Subaru there's often two wires you connect together to make the Check Engine Light flash out the trouble code. On Volvo there's a test box in the engine compartment with its own code display LED. On later Chrysler products you just do the "key dance" (on-off-on-off-on) and read the code(s) on the odometer display.

Unfortunately, the trouble code is only a clue to what the real problem is, and often provides no more than rough guidance as to where to start troubleshooting.

Also, even when the trouble code points exactly at the failed component you can be in for no small adventure on the way to resolution. For example, the time I logged a p0340 and just threw a new cam position sensor at it, only to log a p0344 five minutes after the replacement. Trading in that sensor for a different one resulted in a series of intermittent p0340 and p0344. After a couple of weeks of swapping parts around and tracing circuits and checking grounds I got a different brand of cam sensor at a different store. Problem solved. Note to self: beware of N.E.W. (Never Ever Worked) syndrome with EFI parts and sensors.

Thanks, Bob K.

An old Dodge Ram 50 (made by Mitsubishi) had a "Check EGR" light that looked a lot like "Check EGN". For years, I thought it simply meant that the light was malfunctioning until I actually asked once when I was getting my oil changed at the dealer. They replaced the EGR, and the truck ran noticably more smoothly.

Also, my '05 Chevy Cavalier has a "check engine" light that I think means "you just got bad gas". At least, I know it turned on right after I filled my tank and turned off within five miles after the next tank.

[Casey]

Originally Posted by BoKu

you can coax the ECU to display the OBD codes directly. On Subaru there's often two wires you connect together to make the Check Engine Light flash out the trouble code. On Volvo there's a test box in the engine compartment with its own code display LED. On later Chrysler products you just do the "key dance" (on-off-on-off-on) and read the code(s) on the odometer display.

Unfortunately, the trouble code is only a clue to what the real problem is, and often provides no more than rough guidance as to where to start troubleshooting.

Also, even when the trouble code points exactly at the failed component you can be in for no small adventure on the way to resolution. For example, the time I logged a p0340 and just threw a new cam position sensor at it, only to log a p0344 five minutes after the replacement. Trading in that sensor for a different one resulted in a series of intermittent p0340 and p0344. After a couple of weeks of swapping parts around and tracing circuits and checking grounds I got a different brand of cam sensor at a different store. Problem solved. Note to self: beware of N.E.W. (Never Ever Worked) syndrome with EFI parts and sensors.

Thanks, Bob K.

Truth. On my car (a '93 BMW 318), you put the key in the accessory position, and floor the gas 5 times. It can be useful, but there is one code that's the bane of my existence. 1286.

1286 is a knock sensor failure code. Problem is, according to the book, I can only actually get this code on a certain set of engine control modules. Mine is the run directly before those, so there's no reason I should be getting this. The dealership has checked, the knock sensors are fine, and thankfully it's not one of the codes that turns the Check Engine light on.

Ca "Lambda sensor... knock sensor... come on... ping sensor! Bad gas!" sey

[jimmy101_again]

Originally Posted by TatorKate

The only time I have ever encountered a "check engine" light ended in financial disaster. Once upon a time (the time was actually 3AM), in a land free of cell phones, I looked down to see a tiny illuminated icon. By the time I had figured out what it said, the engine had died. I took the walk of shame to a pay phone. After a humiliating phone call, a morning tow, and a mechanic's visit, I was informed that my timing belt had broken. I don't know which was more shocking-the $1000 bill or the realization that there is a car part called a timing belt. For those of you with a timing chain- don't rub it in. Suffice it to say, I am now terrified of the "check engine" light/icon/whatever.

In this situation I don't think the check engine light really makes any difference. It wouldn't have mattered if you had immediately shut off the engine, you would still need the $1000 timing belt replacment.

That's assuming the light indicated that the engine actually detected a problem (like the belt stretching right before breaking).

If the light is based on mileage and came on because it was time for a regular service interval ... well that shouldn't have mattered either. Even if the car was at the sceduled belt replacment interval the belt should't fail within a few seconds of exceeding the interval.

Looks to me like you did everything OK with the possible exception of exceeding the replacement interval for the belt. You would normally have to be many thousands of miles beyond the replacement interval for the belt to actually fail in service.

[WildaBeast]

Originally Posted by jimmy101_again

In this situation I don't think the check engine light really makes any difference. It wouldn't have mattered if you had immediately shut off the engine, you would still need the $1000 timing belt replacment.

$1000 sounds like a awful lot for a timing belt replacement (although I have no idea how much it costs; I'm one of those people with a car with a timing chain). I'm guessing most of that was to repair the damage caused by the timing belt breaking. On some cars when the timing belt breaks the valves get destroyed.

[Latiam]

My check engine light means the emissions control system is not working, or the gas cap is loose, or I just drove through a big puddle.

I don't know what else the car does if it's another problem, but usually I bring it in every six months for a semi-annual checkup so it's not so much a problem. I only call when it's making noises.

BTW, it's just a picture of an engine. Saturn Ion 2005.

[snapdragonfly]

Originally Posted by WildaBeast

$1000 sounds like a awful lot for a timing belt replacement (although I have no idea how much it costs; I'm one of those people with a car with a timing chain). I'm guessing most of that was to repair the damage caused by the timing belt breaking. On some cars when the timing belt breaks the valves get destroyed.

I can't remember whether my Dodge Caravan has a belt or a chain: I didn't know there was a difference. But I do know that you damn sure do want to replace it *before* it goes out; it's one of those things that when your mechanic says, "you got 65,000 miles on your car and your timing belt is supposed to be replaced at 60,000" you go ahead and do it. I can't remember what it cost to replace it on my car either; I think it was a few hundred. But the cost to replace it after it breaks is definitely due in large part to the damage it causes by breaking.

Your owner's manual should tell you how often to replace it. I think in fact my Dodge is due to have it replaced again as it's got 200,000 miles on it. (that's what you get when you change the oil faithfully and have the luck not to get a lemon in the first place. Knock on wood.)


My "engine light" sensor experiences have meant either a) your emissions control sensor thingie needs fixing or b) your engine light sensor needs fixing.