Question about 2004 Honda Odyssey

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The Check Engine Light comes on, diagnostic code indicates gas cap or two other possible causes. I have replaced the gas cap twice and still have the indicator on. I disconnected the battery and drove

The odometer is 140,000 miles.

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Maybe the filler cap...if not thigtened 3 clicks after filling, check engine light may come on... Sometimes we forget about it

Posted on Apr 21, 2014


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: resetting honda civic check engine light

watch this free video on how to diagnose and reset your engine light if video dosent work go to

Posted on Oct 25, 2009

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SOURCE: engine light comes on, have had solenoid replaced

sounds like you have a leak in EVAP system need to have tested to find leak they make a smoke machine to test

Posted on Jan 29, 2010

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SOURCE: Check engine lite comes and goes after new O2 sensor installed?


Posted on Apr 17, 2009

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Check engine light is on and egr valve was replaced and the light came back on after 3 miles - what are other possible causes? gas cap seems fine

What DTC - diagnostic trouble code is stored in the engine computer ? You can take it to most auto parts stores an they will check it for free !

Aug 19, 2015 | Cars & Trucks

1 Answer

Gas cap light and check engine light on 2001 ford taurus ses

Sorry, but there is no "sensor at the fuel cap". Therefore, there is no code that says "sensor at the fuel cap". There is, however, a Diagnostic Test Code (DTC) That indicates a possible problem with the fuel cap.
(HINT: When you want information on codes, it is usually wise to include the code number that you are getting - that way, it can be looked up, instead of GUESSING at what the problem is from a code description that some generic code reader is telling you..)
DTC P0457 is defined by SAE J2012 as "Evaporative Emission System Leak Detected (fuel cap loose/off)"

At this point, I am ASSUMING this is the code you got.

This DTC is set when the Powertrain Control Module (PCM) detects that there is an in-tank pressure drop that is more than 7in. H2O within 30 seconds directly after refueling, or there is excessive purge (fuel Vapor) flow more than .06 lbs. per minute. Possible causes are:
> Fuel filler cap not installed after refueling
> Fuel filler cap loose or cross-threaded

There are other malfunctions that can also cause this code to set, but it will be accompanied by other codes indicating other possible failures.
If there are no other Evaporative Emissions System codes present, then there is most likely a problem with the way your fuel cap was put on the last time you got fuel.

Check your fuel cap and make sure it is on correctly and is tight.

Apr 18, 2012 | 2001 Ford Taurus

1 Answer

My 2001 Ford Escort ZX2 service engine soon light comes on and says I have a faulty gas cap or a vacuum leak?

It would be really nice to know EXACTLY which code you are getting. However, since you mentioned gas cap, I will assume that you are getting Diagnostic Test Code (DTC) P0457.

First, you need to understand that DTCs (or fault codes) NEVER tell you what parts to replace. They only tell you which of the many circuits and systems monitored by your onboard computer network is malfunctioning. The circuit or system must then be properly diagnosed to determine the actual CAUSE of the failure. To do that, you need to follow the correct diagnostic procedure and you also need to know how the system is supposed to work, so you will know a malfunction when you see it.

Here is what is causing your confusion:
The standard definition for DTC P0457 is "Evaporative Emission System Leak Detected (fuel cap loose/off)"
Please note here that the part about the fuel cap is in parenthesis. The MAIN description is "Evaporative System Leak Detected." This fuel cap part is only because this code is very often caused by people not putting their fuel cap on correctly, forgetting to put their fuel cap on at all or losing it, or refueling their engine with the engine running. So, this part of the DTC description is NOT telling you to replace the gas cap. It is only telling you to check for a loose or missing gas cap for a possible cause because it is so common.
What the code REALLY MEANS is that there is a HUGE leak in your EVAP system.

Please also note that a fuel tank pressure (FTP) sensor that is not working correctly can also cause the computer to "think" that there is a huge leak when there is not...Hence, the need for proper diagnosis.

The operation of the FTP needs to be verified to make sure it is not "lying to the computer. All of the hoses, lines, tubes, charcoal canister, and other components of the EVAP system need to be inspected for cracks, tears, breaks, etc. that would cause a leak in the system.

Feb 03, 2012 | 2001 Ford Escort ZX2

1 Answer

What causes the check engine light to come on in a toyota echo 2004

take it to autozone and have the fault codes read for free
the charcoal cannister that they speak of is the EVAP cannister and if there is a problem with it it will show as a fault code
it has a purge valve and a purge valve solenoid for operation , both of which can be replaced separately
when you hear" I think " , time to find an accredited service center that has experience on your make pf vehicle and get a second opinion
the gas tank neck is a rubber section and comes up in the code as a small leak
a simple loose gas cap will put the light on

Mar 26, 2017 | Cars & Trucks

2 Answers

My check engine light is on 2002 325ci .....mileage 190,000..what to do ?

The information below was complied by me, it explains what causes the check engine light to come on and the process of finding the cause.

When the Check Engine light (or Service Engine Soon) is turned on, the systems computer control unit (called the PCM) has sensed a fault in the electronic controls of the engine and/or the emission system. When this happens you will seldom feel the car engine run any different. There are about 200 possible system faults (the gas cap is just one of them) that turn the Check Engine light on, to know what has developed a problem you must have the system tested, this is called an OBD2 fault code test, Kragen/Oriley and Autozone parts stores (USA only) do this testing for free.

Hope this makes things a little clearer, it doesn

Sep 14, 2011 | 2001 BMW 325

1 Answer

2002 dodge durango engine light on. after diagnostic test.results indicate evaporator hoses are leaking

Check your gas cap first.

Replace the cap and have the code cleared at Autozone. If the problem comes back, look for cracks in the lines between the gas tank and the evap canister behind the battery.

Nov 11, 2010 | 2002 Dodge Durango

2 Answers

Check engine light came on. Code P1456.

Did you change the gas cap with a Honda gas cap? Tighten it at least three clicks?
Also, Honda recommends that you never top off the tank when getting gas (only go to the click-off of the pump; otherwise you can get back flow into the system that will cause the code).
Tightening or replacing the cap will not immediately cause the light to go off; it can take up to three days of driving for the light to reset.
To check if your readiness codes (emission system) are set, turn the ignition to ON (II), without starting the engine. The Malfunction Indicator Lamp will come on for 20 seconds. If it then goes off, the readiness codes are set. If it blinks 5 times, the readiness codes are not set.
You can, of course, try resetting your engine light to see if it will come back on (which it probably will). I believe the procedure is:
Turn off the engine.
Press and hold the Select/Reset knob (odometer) in the instrument panel, then turn the ignition switch to ON (II).
Hold the knob for approximately ten seconds until the indicator resets.

Hope this helps you.

Nov 17, 2009 | 2004 Honda Pilot

2 Answers

Check engine light on, ignition coil diagnostic

i would start with the gas cap and have them read the
code again. its a cheaper way to go first

Apr 09, 2009 | 2004 Dodge Ram 1500

2 Answers

Check Engine Light

sounds like you have a code for evap leak detected. thats why you have been told to change the gas cap. this means you have a vapour leak in your systam. check all line and hoses to and from gas tank for leak. the filler hose and lines may be leaking. good luck please rate this.

Jan 29, 2009 | 2001 Pontiac Sunfire

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