Check Engine Light

P1491 Rad Fan Control Relay Circuit

If your car and/or truck came with a Catalytic Converter from the factory then, yes. Vice Versa, if it did not, then no.

i belive it's a simple as the 03' method. key in ignition off, hold down tripometer, turn key to on but not running. than hold till the light turns off. but my light wont turn off. and than you have to turn the key off to finish the reset. the Honda dealer told me this procedure it worked twice but now it doesnt.

Try starting the car instead of just turning the key. That worked on my 2001 Civic LX.

I have a 2007 MINI and my check engine light has been coming on and going off since I bought it. I've had the car for 2 years and now have 18,000 miles. The car was recalled to have the catalytic converter replaced and the check engine light still comes on. It will stay on for days and then go off for days. I thought replacing the catalytic converter would take care of the problem but it obviously didn't. The tech at MINI told me that the best gas is Shell and that other gas could cause this to happen. I don't think that's a good enough answer. I'll be bringing my car back for service because of this continuing issue.

What engine light? If you are referring to the check Engine Light, then the computer has detected a problem that effects the emissions controls.

The check engine or service engine soon light comes on to alert you that there is or was a problem with the emissions system on your vehicle. If the light comes on steady and stays on, it means that there is a problem and you should have it checked out soon. If it comes on and flashes, it means you will cause damage if you continue driving.

Without a code reader (you can buy one for about $80 at most auto parts stores), you can sometimes erase the codes by disconnecting the battery cables.

Most newer code readers allow you to erase the computer memory.

The CEL is on because there is a problem in the system. You can turn it off by disconnecting the battery for 10 minutes,but the light is going to come right back on when the PCM sees the problem gain.

There are literally hundreds of possibilities as to why a check engine light(CEL) comes on. The system would have to be scanned to retrieve whatever fail codes there are. Then we would use a manual (that is literally 3 inches thick)that contains flow charts with pinpoint tests, using a voltmeter, to hand diagnose, and find out what is wrong. This process can take a few minutes, it may take a couple of hours, depending on what is actually wrong.

Now here is the "why" of a CEL: What is actually turning on the CEL is the Powertrain Control Module(PCM), commonly known as the engine control computer. Inside of a PCM there are actually two separate systems. One is control, the other system is diagnostics. PCM diagnostics acts as "big brother," constantly looking over the shoulder of the control side of the PCM. Diagnostics is constantly monitering systems to see if the expected voltages and values are present.

Here is an example: If the PCM diagnostics knows that it has been so many minutes since the engine was first started, then the engine temperature should be around 195 degrees. In our senerio, if the engine is still 160 degrees, it sees a problem, and sets the CEL. The technician has to use pinpoint diagnostics to see if we have a stuck thermostat, if the Engine Coolant Temp(ECT) sensor if sending a false signal, if the wiring between the ECT and the PCM is bad, or if the PCM is faulty and interpreting the signal received from the ECT incorrectly. But the PCM is not capable of monitering everything all at once, so it basically goes down a checklist, over and over again, as you are driving down the road. Sometimes a problem can come and go intermittantly, at the right times so as to avoid detection by the PCM.

That is why sometimes a CEL doesn't always come on everytime there is a problem. Sometimes you can unplug a sensor even while the car is running, and it takes a while for the CEL to come on, just because the PCM diagnostics hasen't gotten back around to looking at that area yet.

Our senerio only talked about one area that a PCM moniters. There are dozens of sub-systems that the PCM looks at, and dozens of possible failures within each of those sub-systems, that could cause a CEL.

The easiest way is to purchase a code reader and follow the directions in the included handbook. They give you the module to plug in and a listing of the codes and their meanings.

The computer has detected a fault with one of the electronic components and is warning you to run a diagnostic test.

I had the same problem, it was the distributor cap, (must have had a hairline crack that i couldn't see). Changed it and the check engine light went out and it started again when it was wet outside, one you could check for is bad spark plug wires. Moisture may cause spark to jump causting misfire.

.........................ANYTHING THE COMPUTER IS HOOKED TO CAN TURN ON THE LIGHT..................................... The M.I.L.(Maintenance Indicator Light) is a version of the same thing known as a S.E.S.(Service Engine Soon) light, and is a means whereby an abnormal condition which the onboard computer has detected causes a visual signal to the operator to show. Whenever the computer receives a signal from a sensor that is out-of-range from its programming, this lamp will illuminate; and, so long as the condition persists, and does not correct itself, the light will stay lit--- depicting that a 'hard code' has set in computer memory. Whenever a scan-tool is hooked to the diagnostic link in the vehicle, the primary reason is to 'read the codes'; which, interpreted, means extracting the recorded code numbers for the purpose of identifying what the computer has detected, in order to isolate a problem condition and effect a proper repair. When this light comes on, it is a sign that something has occurred which the computer 'thinks' is wrong. The reason for the computer to 'think' this may be a legitimate problem; or, some condition which IS normal(but unanticipated) may have caused it. For example: If the Oxygen sensor is reading high or low, this could indicate a vacuum leak, a fuel problem, a wiring problem, a clogged air filter, an exhaust leak, high fuel pressure, a bad sensor, etc.; and, if the variation in signal from this sensor is small, the same code could set. The light would come on. And, the 'problem' may be that the driver is making little use of the accelerator, traveling on level road, on a highway, at constant speed, in the middle of the night. This would keep the oxygen sensor's voltage in the same range for a period of time not normally seen. The range is a GOOD range; but, the fact that it is out of the norm by virtue of a time factor would set a code. In such a case, the computer was 'fooled'. This is why it is important to have the codes read by someone who can make the determination whether the codes are a sign of trouble or not; and, what kind of trouble may be showing up in the displaying of certain codes.

Disconnect the battery cable, wait few second that reconnect. That will reset the engine light but doesn't fix the problem. if the problem was not fixed the light will come back on.

I just had this problem and took it to my local kia dealer. They found that the fuel filter needed changed. Perhaps this is the problem with yours but before you pay more money than you need to I'd advise you change it yourself and save 100 or so dollars it's simple to do. If your kia is still under warranty take it and and get it diagnosed. Hope this helps.

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You need to have the code read. Go to Autozone and they will read it for free. If I had to guess I would say that your VSS sensor is either giving out or the Pcm is getting bad info from another sensor.

Something's wrong with your engine. You need to plug into one of those diagnostic computer tools, go to a dealer/repair shop/etc. You can buy those code reader things, but they're pricey.

The check engine light comes on and stays on when a problem is detected by the self diagnosis system of your vehicle.

Generally, a check engine light is lit when there is a problem in the emissions or somthing that is affecting the effectiveness of the emissions.

If the check engine light is flashing a misfire has been detected

There is a leak in the EVAP Emission Control System Leak Detected (Control Canister System), many people advise that a loose gas cap is the reason. They are incorrect, loose gas caps produce P1456, EVAP Emission Control System Leak Detected (Fuel Tank System).

The P1457 typically means that you will need to have your vent shut valve on the canister under the car checked. Not something a casual weekend warrior can do. There are several checks that are done to narrow the problem, including vacuum leak tests and electrical tests. Pretty much a professional mechanic job.

Check out this link for more information

http://www.obd-codes.com

An over- 65 weekend warrior certainly can replace the vent shut valve.* The hardest part was getting the car properly jacked and supported. I used the center jack point in the rear and two jack stands. For tools, you need 10mm and 12mm socket wrenches, vise-grip pliers, and a Phillips screwdriver. A 10-mm crowfoot or very short socket will be helpful. There are three bolts (10-mm head) that hold the canister to the car. There are two bolts (12-mm head) that hold a parking break cable bracket. Remove all 5 bolts. Undoing the parking brake cable bracket allows easier access to the canister. The rear-most bolt on the canister is under a cross brace. That is where the crowfoot or shortened socket comes in handy. After the bolts are removed, drop the canister down so you can access the two screws holding the shut valve in place. The screws are probably rusted. Use vise-grips (use ones with teeth on the jaws, if available) to grab the screws by the sides and get them started to turn. A little penetrating oil helped too. Of course, you need to disconnect the electrical connector, which is a typical pinch and pull connector, and the rubber connecting tube. Replace the new valve and reassemble. The valve does not come with the two mounting screws. My Honda dealer was kind enough to give them to me, including new washers.

*The correct name of the valve is as stated above. Autozone had no listing for the shut valve. It has the identical valve, same manufacturer and same Denso number, but calls it a bypass valve. I used the Honda part number and my local store was able to cross check it. The price difference was significant. John4153

Either wire harness or computer. Try bulk head connector at firewall, computer is located behind glove box, cost about $100 at autozone, you have to change out the e-prom from your old unit to new one.

You need to have it checked for codes. YOu will most likely get a code that has to do with the transmission. You can then diagnose that code.

More information is needed as to what it is doing or what it is not doing, too many things can be wrong with this...................

The check engine light (service engine soon) comes on and stays on when a problem is detected by the self diagnosis system of your vehicle. Generally, the problem is in the emissions or something that is affecting the effectiveness of the emissions, but other causes can trigger the light to come on, too. To determine the cause, the vehicle will need to be taken to a parts store or a shop that has an OBD2 scanner, or for 1995 and earlier models, an OBD1 scanner, While a scanner will not give you the magic answer, it will give you a code that narrows down the problem area.

The normal causes for a misfire would be

Faulty: spark plug, spark plug wire, ignition coil, ignition module, fuel injector are the most common. Coolant leaking into a cylinder is another.

Internal engine problems such as burnt valve, broken valve spring, bent push rod, worn rings

First of all you must repair the problem that caused the light to come on in the first place or it will just come back on after being reset. You can try disconnecting the negative battery cable for 5 minutes. This may or may not reset the check engine light. If it does not then you will need to reset it with an OBD2 scan tool.

It could cause the check engine light to come on with a code concerning cooling system/thermostat performance.

It could cause the check engine light to come on with a code concerning cooling system/thermostat performance.

Typically means the computer detected a malfunction with the emissions system. They can also be produced by bad gas, by not properly securing the gas cap, and low battery conditions. If the light is flashing and the engine is misfiring, take your vehicle for service immediately. Otherwise, if you recently got gas, check the cap, or wait for the next tank to see if the issue is resolved. If you noticed the light after a low battery condition or after a jump-start, then drive the car normally for a few days to see if the condition clears up. If after a few days of driving the light does not clear up, take your vehicle in for a more thorough diagnostic check.