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Patch87 November 1st, 2012 12:21 PM

Check engine light Emissions Problem
1 Attachment(s)
I have a 2000 Ford Expedition with I believe a 4.6 liter. I keep getting a check engine light caused by an emissions problem. I replaced the "see attachment" last year the car passed inspection but the emissions problem keeps reoccurring. Any Ideas on how I can Permanently solve this?

JSoko November 1st, 2012 12:25 PM

what is the code that it throws

Patch87 November 1st, 2012 03:08 PM

P0401 EGR FLOW Insufficient

Booba5185 November 1st, 2012 06:23 PM

The peice you pictured controls the EGR via vacuum, so the problem could also be a vacuum leak, a bad EGR valve, or a bad connection leading to this solenoid (what you pictured). Unplug the vacuum line leading from the solenoid to the EGR valve, and put your finger over the hose while the truck is idling, you should not feel suction. If you do, shut the truck off, unplug the solenoid, start the truck up and put your finger on the hose again. If you still have suction, then the solenoid is indeed bad and you need to replace it with a better brand.

If you unplug the vacuum line going from the EGR solenoid to the EGR valve and do not have any suction on the vacuum line (while the truck is running), then get a small length of (clean) hose, connect it to the EGR valve and suck on the hose (with a vacuum pump or your mouth). The engine should run like poop when you do this aand damn near die. If it makes no difference, then the problem lies inside of your EGR valve. It's clogged, or down right bad.

If you suck on the hose and the engine DOES fall on it's face and die, then the EGR valve is most likely fine. Reconnect the vacuum line going from the EGR solenoid to the EGR valve. Disconnect the OTHER vacuum line coming off of the EGR solenoid and check for suction. This hose should have suction at all times (as long as the engine is running of course). If there is no suction on that hose, then you have a vacuum leak or the hose itself is disconnected from the engine (intake manifold).

If your truck passes all these tests, then the sensor on the EGR valve itself (which tells the computer if the EGR is moving or not) it most likely bad, and will need to be checked and\or replaced.

glc November 3rd, 2012 12:56 AM

The most likely problem with a 4.6 is plugged EGR passages in the throttle body elbow.

The part you replaced is called a DPFE.

Patch87 November 9th, 2012 10:47 AM

Thanks to all for the great info. I will post when I solve the problem.

JSoko November 9th, 2012 07:25 PM

hopefully it's nothing major

notasinger January 22nd, 2013 05:09 PM

You probably have a plugged throttle body as mentioned above. I have a 99 4.6 with 195,000 and mine was pretty much clogged solid.

jovanlopez90 January 23rd, 2013 02:11 AM

it a common issue could be a clogged egr pasage or the dpfe i got the same code for 8 months now

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