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MCcelica
05-19-2014, 05:14 PM
So. After I got my cat replaced and removed a bunch of other CEL codes for that, I now have a persistent P0440 code. From the research I've been doing, I've gathered a lot of information that a large fuel leak in the evap system is usually what causes this. The information I've read said that it could be a gas cap or filler neck, but those have both been inspected and seal properly, although I'm not opposed to replacing both of those either. Now, since the evap system builds up pressure while sitting or under minimal load and purges during WOT to richen the mix but, more importantly, is also vacuum driven. With that in mind, I'll explain what I know.

What I know:
-P0440 can be indicative of a lot of things including a large evap system leak. Large leak can also be a series of smaller leaks.
-I'm losing roughly 30-40 miles per tank.
-Gas cap/filler neck appear to be in good condition.
-Vacuum hoses have not been replaced in god knows how long.
-Car has over 230k miles.
-There is no odor of unspent fuel.
-Spark plugs read lean, which adds credibility to the idea that the evap system doesn't have extra fuel in it to dump back into the system when under load.
-Running of the engine and idle have not been affected.

What I don't know:
-Where the f**k my fuel is going.

Where would you start?

bloodMoney
05-19-2014, 07:36 PM
It's the chupacabra. Sounds like it. Definitely maybe.

Murgatroy
05-19-2014, 10:25 PM
Buy a Mustang.

Murgatroy
05-19-2014, 10:25 PM
I would start with a gas cap, they are cheap and it is easy (and a possible culprit.)

MCcelica
06-09-2014, 03:45 AM
What I wound up doing is arbitrarily going through and replacing all the evap lines that weren't hard lines. One of them had a no shit open break right where the hard line connected, it just wan't a very big break. This is the one that was coming from the canister to the intake before, the ummm... some fancy evap thingamajig that I can't remember the name of right off. A couple others were missing clamps at least on one end. There was not a single hose that was in actual good shape, though.

It has been a week. It's hard to gauge the fuel consumption because I did drive part of that tank out on the shitty hoses, but as of yet there are no more CELs. Beyond that, the car does perform much better on cold start up than I ever remember it doing. Before, if I were to start up and try to go anywhere right away, it would kind of bog down, but not to the point of stalling. It just wouldn't go anywhere, even mashing the gas pedal. It would do that until it warmed up. Trouble was it still wouldn't do that every time. I've also heard other 7th gen owners thinking that symptom was a TPS, so I didn't include it in my symptoms list for the evap system. What I have noticed since the hose swapping jubilee, is that it no longer hesitates after a cold start.

So I figure that if, by the end of this tank, I haven't thrown any more CELs, and I can get to within striking distance of... say, 380 miles on the rest of this tank, I'm gonna call it good.

underscore
06-09-2014, 11:57 PM
Nice work, fingers crossed you've solved it.

MCcelica
06-11-2014, 04:36 AM
I'm calling it good. I made it to 360 miles before the gas light turned on. I say that's within striking distance of 380. Back when this condition was at its worst, I would barely make 350, and sometimes dropped down to 340.

I've also patched up some wiring on the PS marker lights... here's hoping it stays.

Nitro_Alltrac
06-12-2014, 11:03 AM
Glad to hear that it looks like you found in Seth.

bloodMoney
06-13-2014, 02:41 PM
So no Chupacabra?

little bit? no?

Murgatroy
06-13-2014, 10:18 PM
I had Crisco go over and remove the Chupacabra from the wheel well about a week ago.

CriScO
06-13-2014, 10:37 PM
Little fucker tried to bite my nuts.

MCcelica
06-13-2014, 10:51 PM
Little fucker tried to bite my nuts.

... wait, you have nuts?

Murgatroy
06-13-2014, 11:00 PM
... wait, you have nuts?

As many times as they have been on your chin you should already know this.

We all know how close you and Crisco are, you may act all big and tough, but everyone knows you are the bitch when the doors are closed.

MCcelica
06-14-2014, 04:48 AM
As many times as they have been on your chin you should already know this.

We all know how close you and Crisco are, you may act all big and tough, but everyone knows you are the bitch when the doors are closed.

Well now that it's out, he likes it when I suck my thumb when he hucks it in me dumper...