Code P0440 - DodgeIntrepid.Net Forums - Dodge Intrepid, Concorde, 300m and Eagle Vision chat

avalancha805 · 02-17-2013, 02:46 AM

Does anyone know what the code P0440 means? It use to pop up but after a few days it would go away, but now it's stayed longer. I noticed that my milage has gone down. Help! Thnx

**Adpros** · 02-17-2013, 08:52 AM

P0440, General Evap Failure.

Could be a break in the vacuum supply lead to the LDP or most likely a bad LDP.

tgs · 02-17-2013, 10:25 AM

There are so many points of failure in the EVAP system,
how on earth do you narrow it down and does it really matter
if I'm evaporating a little?

I have a hard time believing this is really reducing his gas mileage.
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.
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**Adpros** · 02-17-2013, 11:40 AM

Quote:

Originally Posted by tgs

There are so many points of failure in the EVAP system,
how on earth do you narrow it down and does it really matter
if I'm evaporating a little?

I have a hard time believing this is really reducing his gas mileage.
.
.
.

Not reducing his gas mileage but, a system that doesn't perform as designed will allow the evaporative system to improperly deal with the raw fuel fumes in the tank. That causes more than needed hydrocarbon emissions from his car.

As for how to pinpoint the failure, it's not usually too hard with the right test equipment. And IMHO yes, it does matter!

I called these items out as the "Usual Suspects".

avalancha805 · 02-17-2013, 12:22 PM

Thnx, I'm going to check see what's going on. My mpg went on avg of 19 to 17.1 according to the OBC.

tgs · 02-17-2013, 07:24 PM

Quote:

Originally Posted by Adpros

Not reducing his gas mileage but, a system that doesn't perform as designed will allow the evaporative system to improperly deal with the raw fuel fumes in the tank.

So, the fumes, evaporate?

LOL

I'm sorry, I couldn't help it...

If the system is not working properly, wouldn't it be similar to leaving the gas cap loose?
What else does the system do besides running the fumes past a charcoal filter before releasing them into the atmosphere?

**Adpros** · 02-17-2013, 08:31 PM

Quote:

Originally Posted by tgs

So, the fumes, evaporate?

LOL

I'm sorry, I couldn't help it...

If the system is not working properly, wouldn't it be similar to leaving the gas cap loose?
What else does the system do besides running the fumes past a charcoal filter before releasing them into the atmosphere?

I'm sorry, I don't get it...

Anyway, some of the "vapors" are sent to the intake manifold depending on the state of the system, and are burned in the regular way. This could be why he's noticed a small change for the worse on MPG.

Coping · 02-18-2013, 02:45 PM

Quote:

Originally Posted by avalancha805

Does anyone know what the code P0440 means? It use to pop up but after a few days it would go away, but now it's stayed longer. I noticed that my milage has gone down. Help! Thnx

I had this code on my 2002 Concorde Limited for over a year. It has the 3.5 High Output engine which should be the same as your 300M. Like you, my mileage went down a bit. Like you, I was unsuccessful at tracking down an evap leak on my own.

It finally disappeared when I replaced my leaking valve cover gaskets. Hasn't come back since.

My gaskets were leaking at the same location on both side of the engine; the outside corners closest to the firewall. I could see it leaking from the top on the passenger side. Getting underneath the car I could easily see the oil dripping down the back of the engine and gathering on the transmission pan. Probably started leaking with 110000 miles on the odometer.

**Adpros** · 02-18-2013, 03:11 PM

Quote:

Originally Posted by Coping

I had this code on my 2002 Concorde Limited for over a year. It has the 3.5 High Output engine which should be the same as your 300M. Like you, my mileage went down a bit. Like you, I was unsuccessful at tracking down an evap leak on my own.

It finally disappeared when I replaced my leaking valve cover gaskets. Hasn't come back since.

My gaskets were leaking at the same location on both side of the engine; the outside corners closest to the firewall. I could see it leaking from the top on the passenger side. Getting underneath the car I could easily see the oil dripping down the back of the engine and gathering on the transmission pan. Probably started leaking with 110000 miles on the odometer.

While I'm pleased you did manage to stop your DTC P0440, I very highly doubt the valve covers had anything to do with it. I have to assume you corrected a vacuum leak or un-pinched the vacuum supply hose to the LDP or possibly NVLD. The presence of this DTC does not necessarily indicate there is a leak in the system. It is very much possible that the LDP or NVLD has simply stopped working properly.

In my area, it is necessary to have these fixed for the annual or bi-annual emissions inspection so, if his locale does not require it then I can see where the idea of skipping the diagnosis comes from.