PO 440 - Code

[ThunderChicken]

Well guys, went back to my mechanic today and code# PO 440 showed up on the computer. I think he is baffled.

He checked the gas cap and vacum lines and nothing. He now thinks it might be a vacum cellinoid. He tells me there is two, one in the engine compartment and the other underneath the VX.

What do you guys think? This is getting a little annoying.

[ThunderChicken]

Researched this a little bit here and it looks like my problem may be the fuel pump or fuel pump related.

I will check the fuse tomorrow and see what happens.
What do you think?

[ThunderChicken]

Have any of you had this problem with your VX? I am taking it back into the shop tomorrow.

I think it may be somewhere in my fuel system. I have the surging, the rev's for no reason, the start thaen die. My check engine light came back on this afternoon.

I don't know what to do now.
Any help would be greatly appreciated.

[Dare2Dream]

The most probable cause is usually the gas cap. I'd say, try to make sure the gas cap is tight (and that the cord is not stuck below the cap). Then reset the code and see if it comes up again. You can reset the code in two ways: unplug the battery for 20 minutes or go to an autozone, loan the code reader and use it to reset the code.

I had this code come up once, it was the gas cap in my case.

If you have the surging revs, then the cause could be different. Once reason for surging rev is an air leak e.g. at the EGR or the air intake. Do you hear any sound when you are accelerating such as the sound you get when you hold a card in the spokes of a bike?

[ThunderChicken]

Thanks for the response. I checked the gas cap last week when I took it in and it doesn't seem to be the problem. I thought if it were the EGR sensor it would show up on the code read out AGAIN.

It did code out the EGR and then it stopped and started coding other things instead.
My mechanic cleaned the EGR but we never replaced it. Could it need replaced now that I had the intake gaskets replaced.

I'm at a loss on this.

[Dare2Dream]

My knowledge is limited but i know one cause of the surging revs is an air leak. I meant to say check for air leaks around the EGR, e.g. a loose/broken bolt or a bad gasket. I don't know if a bad EGR will cause this but a leak around the EGR will.

As I said, if you notice the sound similar to holding a card in the spokes of a bike, then you have a leak. If not, then I have no idea what the problem is. I wouldn't change the EGR unless you knew it is the EGR.

So you replaced the intake gaskets? Was that the original diagnosis by the mechanic?

Anyone else have ideas?

[Hotsauce]

Thats not the code that the egr throws, the egr will throw a false code of low o2 sensor voltage.

I had surging once, but it threw no code. The cause turned out to be the throttle body gasket damaged by where the idle air bypass is.

John C.

[Tone]

P0440 is an EVAP System Malfunction - sounds like the evap hose on the front right of the engine was not connected to the t valve properly. Search for vacuum leaks in that area and follow the hose back behind the engine where it could also have been cut going into the hardline when the manifold was peeled back to install the gaskets.

[ThunderChicken]

Mechanic tells me today that it's a sensor somewhere towards the back of the VX. I don't really know what he is talking about. He told me last week that there are two senosrs that could be causing this. There is one located towards the front under the hood and the other is near the gas tank.

Does anybody know what he is talking about?

[Tone]

Did you check the items I suggested? That is the one that controls the evap back to the cannister near the tank.....

[ThunderChicken]

Yes he did, today.
I just want to get it fixed.