Check engine light

[mithrandir2001]

The check engine light recently started to remain lit on my 2001 Accord as I drive it. I understand this light means that the engine senses that some emissions parameter is out of whack. I just had my car smog-tested 3 weeks ago (annual inspection) and it basically came up all zeros (the engine is a ULEV). It doesn't seem right.

I checked the gas cap and retightened it. I have over 100 miles on the current tank of gas so I don't think this is the problem, but I did it because I've been told this is the most common cause of the light alarms. I've driven the car about 10 miles since tightening the cap. The light remains on.

I called the dealer to schedule an service appointment (the car is under warranty) and they told me to tighten the gas cap and drive the car over the weekend as normal and call back on Mon-Tue if the light remains on. When I told them I didn't think the gas cap was to blame and that I already retightened it, they asked me if the car was running differently and I said no. "Call us back next week if the light's still on."

I don't like driving a car that has a warning light on the whole time but I don't know what to do. Should I take the dealer's advice and just "ignore" it for now? I put my nose near the exhaust pipe and I don't smell anything funny or see visible fumes. I'm just looking to cover my @ss.

 

[guyver01]

The formal name for the "check engine" light is the "MIL" light, or Malfunction Indicator Lamp. And that's precisely why it's there -- to warn you that something is not right with the powertrain management system.

This light does not indicate the potential for an immediate, catastrophic failure, which would be the case if the oil pressure warning light or the temperature warning light came on while driving. The "MIL" light comes on when the PCM (powertrain control module) detects a fault code in the system. This can be as simple as a sensor providing an out-of-spec signal or a failed sensor, to a more serious wiring/harness/connector problem or a major failure in the system.

Since the early 1990s, the PCM also monitors and controls transmission operation and performance, so the light can indicate a transmission problem, as well.

 

[ElFenix]

most likely a sensor is fouled, which usually doesn't do anything to the reliability or performance of the car

 

[iamwiz82]

IIRC, EGR valves have a tendency to go out on those models.

 

[PsychoAndy]

Originally posted by: mithrandir2001
The check engine light recently started to remain lit on my 2001 Accord as I drive it. I understand this light means that the engine senses that some emissions parameter is out of whack. I just had my car smog-tested 3 weeks ago (annual inspection) and it basically came up all zeros (the engine is a ULEV). It doesn't seem right.

I checked the gas cap and retightened it. I have over 100 miles on the current tank of gas so I don't think this is the problem, but I did it because I've been told this is the most common cause of the light alarms. I've driven the car about 10 miles since tightening the cap. The light remains on.

I called the dealer to schedule an service appointment (the car is under warranty) and they told me to tighten the gas cap and drive the car over the weekend as normal and call back on Mon-Tue if the light remains on. When I told them I didn't think the gas cap was to blame and that I already retightened it, they asked me if the car was running differently and I said no. "Call us back next week if the light's still on."

I don't like driving a car that has a warning light on the whole time but I don't know what to do. Should I take the dealer's advice and just "ignore" it for now? I put my nose near the exhaust pipe and I don't smell anything funny or see visible fumes. I'm just looking to cover my @ss.

AFAIK, the onboard computer is going to store all the fault codes in memory. You're still under warranty so I wouldnt worry about it. When the dealer plugs in a code reader (Is a 2001 accord OBDII?) they should be able to diagnose it.

-PAB

 

[psteng19]

Heh, I've been running with the CEL light on for a couple of weeks now, and I plan to continue doing so until I can afford to fix it.
The thing is, I know the cause - broken O2 sensor in my cat.
Other than that, the car runs perfectly fine, with ups and downs in my gas mileage.

Heck, this is the second time it's happened to me.
The first time my front O2 sensor went bad, I drove months before doing anything about it.

 

[Jzero]

I checked the gas cap and retightened it. I have over 100 miles on the current tank of gas so I don't think this is the problem, but I did it because I've been told this is the most common cause of the light alarms. I've driven the car about 10 miles since tightening the cap. The light remains on.

I called the dealer to schedule an service appointment (the car is under warranty) and they told me to tighten the gas cap and drive the car over the weekend as normal and call back on Mon-Tue if the light remains on. When I told them I didn't think the gas cap was to blame and that I already retightened it, they asked me if the car was running differently and I said no. "Call us back next week if the light's still on."

It may have been the gas cap. I was under the impression that if the gas cap isn't properly tightened and you start the engine a few times with it loose, the light comes on.
Thing is, they told me the light will stay on, EVEN IF YOU TIGHTEN THE CAP! This is a 2002 Civic, so it may be a little different, but....

I would take it to the dealer at my earliest convenience to get it reset and checked out to make sure it was just a loose gas cap, but I don't think it's undriveable.

 

[Doggiedog]

My GS300's check engine light always came on for some reason and it was always for a loose gas cap even though the cap was always put on tight. It would go away after driving for a while though.

 

[ElFenix]

Originally posted by: PsychoAndy

AFAIK, the onboard computer is going to store all the fault codes in memory. You're still under warranty so I wouldnt worry about it. When the dealer plugs in a code reader (Is a 2001 accord OBDII?) they should be able to diagnose it.

-PAB

yeah, its OBDII

 

[teddymines]

When the Check Engine light came on, did you open the hood to check that it's still there?

 

[CraigRT]

With Hondas' the check engine light means bring me in for scheduled service again... the light wont go off until a Honda technician has turned it off. I have a friend that told me this. (she has an Accord)

 

[Jzero]

Originally posted by: Yield
With Hondas' the check engine light means bring me in for scheduled service again... the light wont go off until a Honda technician has turned it off. I have a friend that told me this. (she has an Accord)

There's two lights. One looks like a little motor and that's the OBD light. One is the Scheduled Maintenance light. The Maintenance light can be turned off by the driver. Look in the manual. I'm not sure about the OBD light.

I'm assuming he means the OBD light.

 

[sphinctor]

We have a 2001 Civic, and every 10,000 miles (no sooner, and no later) the light comes on and remains on. To me, that is a reminder to take the vehicle in and get it tuned up/checked out/whatever. Anything to cause you to have to take the time out of your schedule so they can reset the light. So, I just reset it myself and I'm fine for another 10,000 miles. To do this, just press and hold the odometer button prior to and during turning on the ignition key to the on position. Keep the button depressed for roughly 10 seconds (or until the light goes out).

Now, if you haven't reached the 10,000 mile mark yet, you will probably want to go ahead and have it checked out.
That's just my two cents worth.

 

[CraigRT]

Originally posted by: sphinctor
We have a 2001 Civic, and every 10,000 miles (no sooner, and no later) the light comes on and remains on. To me, that is a reminder to take the vehicle in and get it tuned up/checked out/whatever. Anything to cause you to have to take the time out of your schedule so they can reset the light. So, I just reset it myself and I'm fine for another 10,000 miles. To do this, just press and hold the odometer button prior to and during turning on the ignition key to the on position. Keep the button depressed for roughly 10 seconds (or until the light goes out).

Now, if you haven't reached the 10,000 mile mark yet, you will probably want to go ahead and have it checked out.
That's just my two cents worth.

Basically what i was saying... that's what my friend told me.

 

[LordJezo]

I put a piece of electrical tape over mine.

Been on for years now.

 

[mithrandir2001]

For a computer hardware forum, you sure get quick responses to auto questions.

So you're saying the light could mean a problem somewhere between a variety of systems? The Accord owner's manual states that the check engine light has to do with emissions. It doesn't explicitly say "only" emissions but it doesn't mention any other system that will set off the light.

As jzero said, the manual says the light will remain on after tightening the cap. "Drive the car at least 3 trips to reset the light". Kinda strange, I guess.

 

[The Stigenator]

if it was your gas cap.. then in 30 miles it should go out since you tightened the thing.

It normally checks every 20 - 40 miles for engine state.

 

[mithrandir2001]

Originally posted by: Yield

Originally posted by: sphinctor
We have a 2001 Civic, and every 10,000 miles (no sooner, and no later) the light comes on and remains on. To me, that is a reminder to take the vehicle in and get it tuned up/checked out/whatever. Anything to cause you to have to take the time out of your schedule so they can reset the light. So, I just reset it myself and I'm fine for another 10,000 miles. To do this, just press and hold the odometer button prior to and during turning on the ignition key to the on position. Keep the button depressed for roughly 10 seconds (or until the light goes out).

Now, if you haven't reached the 10,000 mile mark yet, you will probably want to go ahead and have it checked out.
That's just my two cents worth.

Basically what i was saying... that's what my friend told me.

That's the maintenance reminder light. Not the same thing.

 

[sphinctor]

Originally posted by: mithrandir2001

Originally posted by: Yield

Originally posted by: sphinctor
We have a 2001 Civic, and every 10,000 miles (no sooner, and no later) the light comes on and remains on. To me, that is a reminder to take the vehicle in and get it tuned up/checked out/whatever. Anything to cause you to have to take the time out of your schedule so they can reset the light. So, I just reset it myself and I'm fine for another 10,000 miles. To do this, just press and hold the odometer button prior to and during turning on the ignition key to the on position. Keep the button depressed for roughly 10 seconds (or until the light goes out).

Now, if you haven't reached the 10,000 mile mark yet, you will probably want to go ahead and have it checked out.
That's just my two cents worth.

Basically what i was saying... that's what my friend told me.

That's the maintenance reminder light. Not the same thing.

Well, on mine the light reads "Check Engine". I just reset it Sunday for the third time.

 

[CraigRT]

Just get the car checked out then... meh..

stupid computer controlled cars.
if it still runs fine, do it whenever it's at your earlist convenience..

 

[Cerebus451]

I recently had the CEL on my Dakota come on. Took it in for service. Turns out a critter had gotten into my garage and was building a nest on top of the gas tank and I think it was an evaporator sensor that was going haywire. They removed the nest and reset the sensor and off the light went. Just to give you an idea of just how many little things can set one of those lights off.

 

[Zenmervolt]

Originally posted by: guyver01
The formal name for the "check engine" light is the "MIL" light, or Malfunction Indicator Lamp. And that's precisely why it's there -- to warn you that something is not right with the powertrain management system.

This light does not indicate the potential for an immediate, catastrophic failure, which would be the case if the oil pressure warning light or the temperature warning light came on while driving. The "MIL" light comes on when the PCM (powertrain control module) detects a fault code in the system. This can be as simple as a sensor providing an out-of-spec signal or a failed sensor, to a more serious wiring/harness/connector problem or a major failure in the system.

Since the early 1990s, the PCM also monitors and controls transmission operation and performance, so the light can indicate a transmission problem, as well.

Hondas use a different method to designate a transmission problem. On a Honda, if there is a transmission problem the D4 light blinks (I'm guessing that the new 5-speed autos will blink the D5 light).

The dealer should be able to extract the code from the ECM without any trouble, sounds like laziness on their part. Call them up and demand that they let you bring the car in. I doubt that the light means anything serious, I've been driving with a failed coolant temp sensor for a while now (fans, etc are controlled by the thermostat, the coolant temp sensor is just used for starting enrichment) and aside from some trouble starting it's been OK. Still, the dealer should be taking a look at the car as soon as they can.

ZV

EDIT: The "Check Engine" light is for malfunctions in the FI/Emissions system only in Hondas.

 

[mithrandir2001]

I think the EPA forces the gas stations in my region to sell special winter gas after November 1. The winter gas has extra additives (MTBE?) to control emissions (since colder engines and colder cats produce more of them). I just fueled up this weekend so maybe that has something to do with it.

 

[Ronstang]

This is quite simple. Reset the light manually. Use the trick with the odometer trip button if this i how it is done on a Honda or simply disconnect the battery for 20 minutes or so. If it was a random fault the light will probably not come back on, but if it does come back one then there is more than likely something out os spec and a simple scan of the codes will net you the info you seek. You might consider picking up an inexpensive code scanner for your car to prevent yourself from being screwed by shops. If it is under warranty then just do this test to verify to yourself and take it in to the shop so they can mess it up further.....HEHEHE....sorry, just joking.

 

[imported_Tomato]

The check engine light in my 2001 Honda has been on for the longest time now. Took it to the dealership and a mechanic, and they said it was just a glitch in the wiring... absolutely nothing wrong with the car otherwise, and it's perfectly safe to drive and handle. Apparently it'll cost $800 just to turn the light off, and I figure it's not worth it. The fact it's on doesn't bother me much, and I can spend $800 on other things...

Peace,
Dezign