Hello All,

The SES light on my 2002 4Dr has been showing up lately. The code is P0400 which has to do with the charcoal canister and the vapor management system. I finally got a chance to crawl under my truck to take a look at it.

I found a flat braided wire that was ziptied to the fuel filler tube. It was completely disintigrated in parts. It seems to end near the cap and start somewhere near the fuel tank.

Anyone have any idea what it is for and where it goes? Not sure if it has anything to do with the P0400 code at all but it seems like a good place to start.

Thanks in advance

 

it's just a ground strap to help prevent arcs (from static) while filling up with fuel, as it's the fuel vapors that are HIGHLY explosive/flammable.

Nothing to do with the code.

Check the vapor line from tank to the front. Make sure there are no leaks, cracks, rusted through...etc
But from what I'm seeing that code may pertain to EGR valve: Either EGR is restricted or one of the spark plugs is walking out/loose

Where did you get the definition of the code?

 

I should probably replace that wire then lol.

I found the definition by searching here and on google.

Where is the EGR valve?

 

You may not have an EGR on your vehicle...'02 is the year they transitioned to NOT having one...and I think they didn't have them through to '05.... IF you do it looks like a mini soup can with a connector coming out of it, sits on top of engine. I'll try to find a pic to post for you.... and if you don't have 1 the chances are 1 or more of your spark plugs are walking out. Probably a good time to pull a few and check them anyway see how they look, especially if you haven't had a tuneup in a while.

I hope this helps, post an update, let us know how you make out.

 

There might be something like that near the back of the engine. I have to look more closely when I can get dirty lol.

I can check the spark plugs. I did a tune-up a few months ago. The info I found said one issue could be that one or more valves that lead to the charcoal canister are stuck and just need to be cleaned. Is the EGR valve one of them?

 

P0400 is a problem with EGR flow. 2002 does in fact have an EGR valve. 2003 through 2005 "X" engines do not. The valve is located top, front, center of the intake manifold. In between the thermostat housing and the serpentine belt idler pulley. Might be worthwhile to remove the valve and clean it out with spray carb cleaner. DO NOT move the pintle valve, unless you want to buy a new EGR valve Install a new gasket with a screen. Most auto parts stores have them in stock.

 

Got a chance to look at my truck. I didn't see anything between the the thermostat and the idler.

The only thing I found is near the rear of the intake manifold. It has a wire harness comeing off it going to a "sensor pressure" that is near the throttle body.

Here are some pictures.






Any ideas?

 

The sensor on the rear of the plenum is the MAP sensor. Definitely no EGR valve on your engine. It's possible that someone installed a 2003 to 2005 engine, which would explain the EGR trouble code. Are there any electrical plugs, near the thermostat housing, that are not connected to anything? Is the 8th character in the VIN a "W" or an "X"?

 

As far as I know it is the original engine. I didn't see any random plugs. 8th charactor is a 'W'.

The SES light started coming on a couple months ago. I have just kept clearing the codes until I had a chance to look at it more.

 

W engine came with an EGR valve. Maybe somewhere along the line the lower intake was replaced due to excessive pitting causing a coolant leak. On the glove box door there is a white sticker with a bunch of 3 character codes: See if it has "Z49", "LU3", and "L35".