: check engine light
09-11-2005, 03:48 PM
I have a 2002 2.7l trep and it now has 103k miles on it. The check engine light came on the other day AFTER I cranked it up. It was just on and has been on ever since. After you crank the car ou will hear a "chime" five seconds after it starts. This is new along with the check engine light.
The "chime" im referring to is the same sound it has when the key is in the ignition. Normally its a fast chime chime chime chime chime etc untill you crank it. Well thats normal it still does that but then after the normally chiming stops count to five and you hear one extra chime.
As I noted this is new along with the check engine illumination on the dash.
Does it mean anything to any of you?
I do not have the money to take it to a service tech and really do not want to purchase a scan tool at this time.
09-11-2005, 06:00 PM
The chime sounds to alert you that an indicator light has just come on. The check engine light or MIL (malfunction indicator lamp) indicates that there is a problem with the engine or emissions system and at least one trouble code has been recorded by the computer.
You may be able to see some codes yourself without a scanner. With the engine off, turn the ignition switch from off to on three times in quick succession. Do not start the car while doing this. If it can display any codes they will display sequentially in the odometer display. If it can't display any codes you will just see the odometer reading as normal.
It is important to know that only some codes can be viewed in this manner. To see ALL the codes that may be set at least a basic code scanner device is necessary.
Possible possible reasons for the check engine light range from a gas tank cap not screwed on tightly to a serious problem that may cause harm to the car.
Good luck and let us know what you find!
09-11-2005, 07:43 PM
ok I will go try the key thing as you suggested. Its funny you mention the gas cap thing cause I just put a locking gas cap on my car the same week this happend.
09-11-2005, 07:50 PM
ok I got this when I did the key 3 times...
09-11-2005, 08:23 PM
P0456 EVAP SYSTEM VERY SMALL LEAK
Very small leak detected in the evaporative purge system
I looked in a few places and couldn't find anything on a P0452
09-11-2005, 08:30 PM
Ok Here's what I've found in the service manual:
P0452 NVLD Pressure Switch Stuck Closed NVLD pressure switch stuck closed.
Evap Leak Monitor 0.020 Leak
A 0.020 leak has been detected in the evaporative
The (M) in the P0456 code says that it will illuminate the check engine light. The other P0452 apparently just set a code and not turn on the check engine light. I have no clue what the NVLD pressure switch is. The Evap system does include your gas cap. That is usually the first place to check when you get any codes having to do with the Evap system.
09-11-2005, 08:37 PM
Ok the NVLD is a Natural Vacuum Leak Detection.
Here's what I've copied for you out of the service manual:
NATURAL VAC LEAK
The natural Vacuum Leak detection (NVLD) system
is mounted on top of the EVAP canister (Fig. 3)
that is mounted on the fuel tank.
The Natural Vacuum Leak Detection (NVLD) system
is the next generation evaporative leak detection
system that will first be used on vehicles equipped
with the Next Generation Controller (NGC) starting
in 2002 M.Y. This new system replaces the leak
detection pump as the method of evaporative system
leak detection. This is to detect a leak equivalent to a
0.0209 (0.5 mm) hole. This system has the capability
to detect holes of this size very dependably.
The basic leak detection theory employed with
NVLD is the 9Gas Law9. This is to say that the pressure
in a sealed vessel will change if the temperature
of the gas in the vessel changes. The vessel will only
see this effect if it is indeed sealed. Even small leaks
will allow the pressure in the vessel to come to equilibrium
with the ambient pressure. In addition to the
detection of very small leaks, this system has the
capability of detecting medium as well as large evaporative
A vent valve seals the canister vent during engine
off conditions. If the vapor system has a leak of less
than the failure threshold, the evaporative system
will be pulled into a vacuum, either due to the cool
down from operating temperature or diurnal ambient
temperature cycling. The diurnal effect is considered
one of the primary contributors to the leak determination
by this diagnostic. When the vacuum in the
system exceeds about 19 H2O (0.25 KPA), a vacuum
switch closes. The switch closure sends a signal to
the NGC. The NGC, via appropriate logic strategies
(described below), utilizes the switch signal, or lack
thereof, to make a determination of whether a leak is
The NVLD device is designed with a normally open
vacuum switch, a normally closed solenoid, and a
seal, which is actuated by both the solenoid and a
diaphragm. The NVLD is located on the atmospheric
vent side of the canister. The NVLD assembly may
be mounted on top of the canister outlet, or in-line
between the canister and atmospheric vent filter. The
normally open vacuum switch will close with about 19
H2O (0.25 KPA) vacuum in the evaporative system.
The diaphragm actuates the switch. This is above the
opening point of the fuel inlet check valve in the fill
tube so cap off leaks can be detected. Submerged fill
systems must have recirculation lines that do not
have the in-line normally closed check valve that protects
the system from failed nozzle liquid ingestion,
in order to detect cap off conditions.
The normally closed valve in the NVLD is intended
to maintain the seal on the evaporative system during
the engine off condition. If vacuum in the evaporative
system exceeds 39 to 69 H2O (0.75 to 1.5 KPA),
the valve will be pulled off the seat, opening the seal.
This will protect the system from excessive vacuum
as well as allowing sufficient purge flow in the event
that the solenoid was to become inoperative.
The solenoid actuates the valve to unseal the canister
vent while the engine is running. It also will be
used to close the vent during the medium and large
leak tests and during the purge flow check. This solenoid
requires initial 1.5 amps of current to pull the
valve open but after 100 ms. will be duty cycled down
to an average of about 150 mA for the remainder of
the drive cycle.
Another feature in the device is a diaphragm that
will open the seal in the NVLD with pressure in the
evaporative system. The device will 9blow off9 at
about 0.59 H2O (0.12 KPA) pressure to permit the
venting of vapors during refueling. An added benefit
to this is that it will also allow the tank to 9breathe9
during increasing temperatures, thus limiting the
pressure in the tank to this low level. This is beneficial
because the induced vacuum during a subsequent
declining temperature will achieve the switch
closed (pass threshold) sooner than if the tank had to
decay from a built up pressure.
The device itself has 3 wires: Switch sense, solenoid
driver and ground. It also includes a resistor to
protect the switch from a short to battery or a short
to ground. The NGC utilizes a high-side driver to
energize and duty-cycle the solenoid.
09-11-2005, 11:36 PM
Thanks a ton Froggy. Its prolly all related to that new locking gas cap.
With gas getting so expensive I didnt want to take a chance on buying for the neighborhood know what i mean....
09-12-2005, 07:32 AM
Did the problem start after you put on the new cap? From what I read, this new NVLD valve was started on the 2002 models and you have to drop the tank to get at it. Try swapping caps with the original and see if it fixes the problem.
09-12-2005, 09:25 AM
Ok I will do that today, but will I need to somehow reset the MIL ?
If so how?
09-12-2005, 09:29 AM
disconnect the battery for 15 minutes
09-12-2005, 09:32 AM
Are you sure? The book totally warns against doing that.
09-12-2005, 09:36 AM
As i understand it, disconnecting the battery resets the computer and in doing so, clears the codes, if the problem still exists, the code will come back. Does "the book" give any reasons not to?
09-12-2005, 10:01 AM
Well it was a Haynes Manual and I cant rememeber what it said exactly. Im at work and its in the trunk of my car so I cant quote it. I brought my truck to work today.
09-12-2005, 10:28 AM
Well, after several restarts, the MIL should reset itself. Here and there, my MIL has come on with a code for the EGR. And each time after about 4 warm restarts, it'll go out again. I have also read that there is a fuse for the computer. I haven't looked for one because I just let mine reset itself.
09-12-2005, 01:50 PM
Well. as I was reading through this thread my first thought on the code was to make sure the gas cap was tight. So after reading it was replaced with a locking cap, I ,too, would replace stock gas cap and see if Check engine light will go out on its own.
09-12-2005, 02:58 PM
I replaced my cap with a locking cap without any problems, did you get you cap from a dealer? If it's not the Gen-u-wine article it might be the cause of your problem...
09-12-2005, 06:05 PM
no its not from a dealer. its from advanced auto parts store.
09-12-2005, 06:14 PM
Sounds like that may be your source then. Try putting the factory one back on, or if you don't have one, getting one from the dealer and put it back on. Disconnect the battery for 15 minutes and see if your check engine light comes back on. It probably won't.
09-12-2005, 08:45 PM
Yup, i'm willing to bet if you got one from a dealer you'd be set.
09-14-2005, 06:24 AM
Not to stael your thunder Digerati, but what fault codes are:
My check engine light just came on this morning.
09-14-2005, 07:49 AM
P0340 = Camshaft position sensor circuit..bad or crudded up sensor
P1684 = battery disconnected within last 50 starts
Resetting the ECU only takes 60 seconds of disconnect, or less.
Not 15 minutes, or 45 minutes, or a full moon.
09-14-2005, 08:36 AM
Thanks Alaryokie!! But HTF would I go about fixing the P0340 fault?
09-14-2005, 10:12 AM
Put in a new camshaft position sensor. Do a search and i am sure its not that difficult to do. You should find some assistance here with that.
09-15-2005, 02:26 PM
Ok I installed the OEM gas cap and reset the code by disconnecting the battery for 15 mins.
The MIL light has not come on since.
Today I think I will add the Locking Cap back and ride for a few days and see if the MIL comes back on.
09-15-2005, 02:40 PM
my check engine light has been on for while now and the key thing shows nothing. i do get 5 beeps after turning the key 3 times, but the light stays on. replacing a gas cap had previously fixed the problem with the light but now no codes at all.
09-15-2005, 03:18 PM
A year ago I changed my gas cap to a locking one from Napa Auto Parts. They had two types of locking gas caps. I went with the more expensive one.....like $8 just so I won't come across these kind of problems in the future.
Not to hijack your thread or anything as I'm not asking what any code means, but last night my check engine light came on as I started up the car. I turned off the car, and then started it up again only to find the check engine light is gone. This morning I checked for codes, and nothing popped up except the battery disconnect code.
My Intrepid runs great...........I wonder why the check engine light came on so shortly? No codes, so I hope no problem.
09-15-2005, 06:43 PM
Mark, Mine does that every now and again. I'll get a check engine out of the blue and after a couple restarts its gone. Always get the same 2 codes P1684 for the battery and P0406 for the egr sensor. Haven't noticed any problems at all. Weird it just comes and goes very infrequently.
01-05-2007, 04:49 PM
A few weeks ago I had a svc. engine light (P0451 code purge monitor). Took the car in, had it inspected & replaced.
Today I'm getting a report that the natural leak detection system detects a problem.
Wonder if the reason I'm getting the light (again) is related to the earlier service I had done. I take it both have something to do with the solenoid and b.s. California emissions laws. These freaks at Midway Chrysler want 290 bucks - my G*d.
01-05-2007, 05:29 PM
The new code is P0441. (Last one was P0451 a month ago). This is the LAST time I plan to get anything with the emissions codes serviced. I'm so pissed. I want the good old days of cars back, before my car turned into HAL from 2001: A Space Odyssey and when I could fix the damn things myself. DAMN IT!
04-23-2011, 11:45 AM
one of my older posts...
04-24-2011, 01:38 AM
disconnect the battery for 15 minutes
While that will work pulling the two red fuses on the far right(driver side) of the fuse box will accomplish the same thing without resetting all custom settings (radio presets, any changes to the lock/unlock sequence or beeps from stock, etc.)
04-24-2011, 03:38 AM
holy old thread