What should I do if my check engine light appears?
Note the appearance of the light. Then note if it stays lit the entire time you are driving your vehicle. Then note if it also lights up the next time you start up your vehicle...and the time after that.If you've driven the vehicle through 3 full consecutive "cycles" (start up, warm up, driving a minimum 15 minutes in normal conditions, shut down and cool down), and the light stays lit for all 3, then you may safely conclude that the OBD (on board diagnostics) system has noted something is wrong with your engine, even if you have not been able to notice a problem.Next thing you ought to do is take your car to a dealership, service garage, or even a "shadetree mechanic" friend with an OBD scan tool. This is a special type of "test instrument" that plugs into a data port on most cars made in the last 25 years or so. Not all OBD scan tools are compatible with all cars, which is why I suggested going to a dealership first.The scan tool will read the error code stored by the cars "computer chip", a digital device that monitors the engine and keeps constant record on whether or not everything is running according to specs.For instance: say you've got a 2000-ish model Chevy Cavalier. Your check engine light goes on, and you take it to a GM dealer to have the OBD codes read. They plug the OBD scan tool into a port under the steering column and the tool reports say..."P0440". Does that tell them what's wrong?Nope. The full entry for code P0440 in the OBDII GM code list is: "Evaporative Emission Control System Malfunction". So that doesn't explicitly state what the problem is...but it does tell them where to look.BTW, the actual trouble could be anywhere from an old gas cap with a poor seal, to a disconnected hose on the EEC tank, to a failure of a solenoid in the fuel system. All three faults will trigger the check engine light...but none will really interfere with the drive-ability of the car. At least, not immediately.OBD scan tools are available for the automobile owner, and there are pages online where you can get the code entries.P0440 Evaporative Emission Control System MalfunctionA typical OBD II scan tool available at retail stores:Autel AL439 AutoLink OBD-II/EOBD Electrical Test Tool - Walmart.com
Check engine Light ON with Code P0422?
Hi, I bought a Hyundai Accent 2000 a week back. The check engine light came on 3 days back. I took it the Auto tune and they said it is code P1128 and the MAF sensor needs replacement. I paid 450$ for that and the light went off. The very next day the light came on again and this time with a different code P0422. This time they said the catalytic converter needs replacement and they quoted 927$ for that. I said no and took the car back. Local mechanic said this might be due to O2 sensors and he quoted 300$ for that. I dont feel any thing wrong with the car. It drives well and gives me a decent mileage for its age. Do I really have to replace any thing? Can any one help me out with this? Thanks in advance, KRSNA
2000 chevy malibu how do I check engine codes?
I know I can take it to almost any auto part store to get it read but I don't live close enough to one to have that convenience. I know most vehicles can be read by making the light blink the codes but I can't figure out the trick on this car. I've turned the key off 3 times and back on nothing. So I tried 5 times still nothing. What I am doing wrong?
Why did my car shake and the check engine light flash while stopped at a light?
What you experienced was almost certainly a misfire event and the cause may be recorded as a diagnostic trouble code (DTC) in the engine controller’s memory. Most failures that are significant enough to cause MIL illumination will record a trouble code and its environmental/ data information from the moment, even if the MIL is no longer lit. Onboard Diagnostics work constantly to keep the MIL off, looking for a reason to turn the CE light out if the condition hasn’t been seen again recently, eventually even erasing trouble codes if all’s good. I can only speculate on the nature of your event, but a thorough scan to retrieve codes and freeze frame data of the moment will often shed some light on the situation.Misfires come in many flavors, ranging from slight loss of performance in a single cylinder, to one or more holes being completely dead. Your description of shake at an idle implies a power imbalance, which usually involves complete loss of performance, but just one hole.Barring an at-home scanner being available, rolling the ignition key from LOCK to RUN three times, then leaving it in the RUN position at the end will initiate the customer code-read feature, spilling any matured codes stored in the PCM through the instrument cluster’s odometer window. All codes will be four digits in length, beginning with the letter P, such as P0123. DTC information can be found at OBD2-OBDII Engine Light Trouble Codes Definitions, Description and Repair Information online.One-trip failures - those that have not quite matured - will not be displayed in this feature, but will show up on a high-end scanner if present.If only a single cylinder misfire code is retrieved, pull the coil and spark plug to inspect for signs of flashover - black marks on the upper spark plug insulator and inner coil boot that will not scratch off with a fingernail. Flashover is pretty common on coil-on-plug ignition systems and the cure is to replace both the boot and spark plug together. Worn plugs tend to incite this sort of situation as spark will always seek the path of least resistance.If your DTC list includes an injector control circuit code that matches the cylinder of misfire, chances are good that the injector is at fault. The injector may test as completely normal when cooler, but will go to an open circuit once heated, either naturally or with a heat gun.
How long does it take to fix a check engine light that keeps appearing when there is nothing wrong with my car
there IS something wrong causing the check eng. light to come on. in some cases the computer needs to be re-programmed, or a specific circuit need re-calibration, but usually there really is a fault, and a good technician can find it. you need to make sure to bring the car in while the light is on. some codes will automatically clear themselves with enough drive time, or start cycles. ask what the code is, if it is a evaporative emissions code, be sure to tighten the fuel cap all the way...at least 3 clicks. there is no logical reason to leave the car for 3 days, unless they need that time to find the problem. i would try a different shop, as they seem to be b.s.'ing you.
My '99 VW Beetle has a Check Engine Light on and 3 Cylinder Misfire codes - What's wrong with it?
Sorry it took me so long to get back to you. It's most likely that the misfires were the cause of the other stuff you had repaired already. If you are around the 90K mileage range I would hope your machine shop guy, or whoever you had do the head job, would have checked for valve leakage and exhaust guide wear. I just did a head job and timing belt / water pump job on an 01 Jetta, and all the exhaust valve guides got replaced, 6 exhaust valves were bent, and 1 intake valve was bent. We had to replace the coils because of the misfire condition like you are listing here. That got rid of the misfires however they had already taken their toll on the motor. I have pics if you care to see them. What that vw service writer says is not a bad way to test it but it's how they tested mine when I brought it in for warranty work (yeah I work on them but why pay when i get a free loaner and a car wash?) They must have forgotten which ones were which since they were unmarked, and replaced the wrong one. I've bitched several times but the service writer (maybe because he doesn't get his hands dirty) insures me that everything is working to VW factory specs. Despite the misfires at idle and the somewhat jerky acceleration. Plus I can hear the sparking inside the head and stumble everytime it happens. Maybe they are just deaf.. but I digress... To do all of that of course you will need tools, not many but you will still need tools. If you have a Mexican beetle (look on the sticker on the door jamb in the drivers side) then there's no wonder you're having these sorts of problems. has your window(s) fallen yet? I would second the "get rid of it" notion stated earlier if you do have a mexican one. Some things made in mexico are fine, just not german cars. Brazil isn't perfect either but apparently the only way vw can afford to sell us cars at the price they do. If you don't feel like screwing with it bring it by and I'll check it out. Coils are only 35 bucks and take nothing to replace if that's the problem. The dealer makes everything sound like open heart surgery and will screw you out of every penny you have. Rob