Check Engine Light

code 26/quad driver module fault. I have a vibration when I acceleration at times. What is the cause? I have a 1990 oldsmobile cutlass cierra, 3.3 liter V6 engine. The engine light comes on and off. what is the possible cause?

Overheated but multiple codes could have come up and more than one possible cayuse. Read trouble codes and start there.

The check engine light being on means that a malfunction has been detected with the emission control system . Have your Mustang scanned for any trouble code (s) in order to diagnose and then repair the problem so the check engine light can be reset

A car and a car's computer that is stated as ECU, their functioning are not inter-relative. Actually, it is just a pre-programmed control given to the car for some specific functions. Some examples are:- Power steering, Power brake, Electronic Fuel Injection Control, etc. So, the non-functioning of the ECU depends only upon the ECU itself. The problems may be:-

1. Whether the ECU's circuit-board is alright or not.

2. Whether it is getting the required input from the car or not.

3. Whether it is doing the processes it is programmed to do or not.

4. Whether it is giving the required output to the car or not.

[img]http://memimage.cardomain.net/member_images/7/web/2551000-2551999/2551515_94_full.jpg[/img]

number 2 is the camshaft position sensor, number three is the camshaft position actuator

From my understanding th replacement is pretty easy. I have not replaced one, so I wont try and tell you how to replace it, however check out www.trailvoy.com for answers to any Envoy/Trailblazer question.

Trouble code P0420 means:Catalyst system efficiency below threshold

The security light might come on while you are driving because it has a motion detector on it and when it senses the cars movement the light comes on.

Disconnect the positive battery cable and wait 30 seconds or so then reconnect the cable. If this does not clear it you have other problems.

A lot of things. Most auto parts stores will check it for free. May take a few stops to find a store that can check a 95 and older.

Bring it to an Advance Auto Parts store and have the diagnose the problem. They hook up the car to their code reader at no charge and will tell you what the problem is.

the check engine light indicates there is a malfunction or problem associated with the engine. instead of just having it turned off, it may be in your, and your cars best interest to find out what and if there is a problem. if the light popped on for no reason, just have the light cleared. You can use an OBD2 scanner to read the code from your cars computer. They cost anywhere from $60 to $300, depending on what features you want. A basic scanner that can also reset the code will run you about $100. As the above states, you should read to code, so that you can determine what is causing the fault. The OBD2 port is located on the drivers side, under the dash board, near where your left knee would be while you are driving. It's pretty big, so you can't miss it. The probe from the scanner will only go in one way. So if it doesn't go in one way, turn it 180 degrees, and try it again.

The check engine light will stay on as long as it is reading a fault code in the diagnostics of your car's computer UNLESS you have a short but that is unlikely. Have you determined what the leak is under your car? The check engine light is normally set when the normal operating functions of your car are interrupted like the engine is not getting enough fuel to the injectors, maybe caused by a weak fuel pump. The check engine light means something is amiss. You can go to some places like Autozone and they may read your diagnostics (download your codes) stored in your car's memory and the codes will tell you what is wrong...........btu nto necessarily what part is at fault. That is why auto techs are paid what they are. You have to be able to diagnose the problem using circuit testers and voltage readings and pressure gauges to try to isolate the mechanical fault. It's not liek old days where you just swapped out parts until you find the one causing the problem. The parts are too expensive now to play hit or miss. Go have someone download your codes and if they have the right handheld scanner they can turn the check engine light off once they clear the codes. Some car will turn off the check engine light themselves if your car goes enough miles or goes through enough starting and stopping cycles to let the computer know everythign is working okay. A weak fuel pump will do this like when it is cold in the morning and the fuel is dense, the fuel pump will pump fuel okay but when the weather and temps get hot the fuel pump has to work harder to meet demand and if it can't, it will set the check engine light. You drive the vehicle on cool or cold days the check engine light will go out because the computer thinks you fixed the problem...............until the fuel pressure drops someday and the check engine light comes back on. Try to identify the leak you have and get the codes read and see if the 2 are connected. If not, then you will need to fix the leak and then track down the problem which could be as simple as a loose gas cap or somethign major like a part of your computer going out.

Yes, the Service Engine Soon light is the same as the Check Engine light.

You can try disconnecting the battery for about 10 minutes. You can also go to any Autozone if you have one locally and they will reset it for you for free. or, you can simply turn your key to the II position on the ignition and your indicator lights should be on. then while still in position II push your trip set button and hold till service light starts blinking,now you have reset your service light for another 7,500 miles.

Since libertys were made after 96 you just need to hook it up to an OBDii code reader to retrieve and reset the codes. Since it aids them in selling parts most parts stores will read your codes for free. This is just an indication of what sensor or system is not reading or operating correctly, diagnosing the exact problem will still be necessary. Some codes are easily interpreted and some leave more questions than answers.

I'd like to add something to this persons answer. If your liberty has a digital odometer you can pull the codes yourself. This is how you do it. Turn the ignition to the on position and push and hold the trip meter setting until it registers zero. Turn the ignition switch to the off position,then turn it to the on position,turn again to the off position and to the on position and this has to be done within five seconds. You should see your codes scrolling on your odometer. When it is finished it will say "done". If you didn't write all of your codes down, repeat the steps. Here's another way. Put key in ignition,push down the odometer reset button then turn key to the on position and release the reset button and the computer will start it's countdown showing you the serial number and then the codes. Hope this info was helpful to all who own Chrysler and jeep autos with digital odometers.

I assume you have a 96 and up vehicle. If the light is blinking and then eventually it will stay on, it's always been a misfire code for me. Take your car to an autozone or advance auto parts and they will read the code for you. It will usually be plugs, wires, or a coil, depending on your car. Hope this helps.

take earth of batt for 5 mins an then put it back on an it resets it

Pulling the ecm, or pcm fuse for a minute or so will reset it, most parts stores have scan tools and will reset it for free, if the light is indicating a problem, and it always is, you will need to repair the problem or the light will just come back on. If you are trying to get the car smogged you will need to drive it about 30 to 50 miles before it will pass.

Try taking the batter cable off for about a min and then replacing it... it should go off unless there is really a new or recuring component problem.

yes it will pass bag lights are exceptional but so long as they are not exposed. or missing. but check engine light should not be on at all ....although if the engine light persists you will be allowed a waiver for one year

No, as long as you tell the buyer it is on.

Any fault that affects emissions will turn the light on. You need to have it checked for codes to know possible causes.

Any fault that affects emissions will turn the light on. You need to have it checked for codes to know possible causes.

With a scan tool after repairing the cause of the code.

With a scan tool after repairing the cause of the code.

A spark plug that is causing a misfire is one of many reasons for the check engine light to come on.

The started putting computers in the bikes a while back. The engine light stays on for a few seconds after turning the ignition switch on to allow the fuel pump to pressureize and the computer to boot up and callibrate. You should NOT start the bike before the light goes out!