I have a early build 6.0 PSD in a 04 Excurson. I got the EX in May of this year. I am the second owner. It has had a on going problem with coking.
The intake has been replaced twice, at least 3 EGR valves and just about every sensor replaced once before I got it.

About 6 weeks ago I got a CEL. Got the code read and it showed a P0401. From reading on this and other Forums I went the cheap route first. I cleaned the EGR valve and installed new o-rings. The valve only had a little bit of soot on it. Nothing like some of the pictures I have seen. I cleaned the EBP sensor and the tube. Again just some soot. Diconnented the batteries for a hour. Hooked battteries back up, no CEL for 5 days. The CEL same back on, P0401 again. Replaced the EBP sensor. Cleared the code and the CEL came back on again in a few days. Replaced the EGR valve and cleared the code and the CEL is back on again, P0401.

What should I do or try next????

I want to do a EGR delete and some other upgrade to the EX. But wanted the wait untill the fall when it cools off.

Thanks

 

Not sure what to tell you but you may have a lemon on your hands.

 

Who replaced the first 3? Dealership or someone spinning wrenches? With that many EGR replaced might want to check for chaffed wiring.

 

All the work was done at a Ford Dealer before I bought it.

 

first thing to check is going to be torn cac boots. This is a know cause of p0401., check ficm voltage this will also cause a p0401.
let me know and we can go from here.

 

Thanks Cheezit, I will check the boots and ficm voltage tomorrow

 

You can also check IAT2 to see if it's really dirty. Is yours a CA emissions vehicle?

I still get P0401 every once in a while. I've been told that with certain strategies, very tiny boost or exhaust leaks will trip the light. The leaks can be hard to track down.

Now when I get the light I check it, clear it, and go on my way. It's a nuisance code AFAIC.

 

I cleaned the IAT2 sensor the first time I cleaned everything, just some light soot on it.
It is a CA emissions vehicle.
It was sold new in Las Vegas and I bought it from a Ford Dealer in Las Vegas.

 

ook with a ca truck you will also need to check the pcv hose that goes to the left valve cover and make sure the green o-ring is there and in good shape.

have you had the truck reflashed in the last 2 years or so? there are some changes to that code's calculation because they were having issues with the software being to sensitive.

 

I have only had the truck since May of this year. I don't know when it was last flashed

 

Here is the history on the Excursion that I got from the original owners after I bought it.
The Names have been ------ out.

1/3/2004: Purchased 2004 Excursion from ------ Ford and purchased 4 year/50,000mile QualityCare Maintenance Protection Plan-Normal ($1310.00) Sticker price $50,570.00
1/7/2004: Repaired right front door molding and Heater Fan
1/13/2004: Brought in to have ordered molding put on.
1/15/2004: Repaired right front and rear door molding
6/11/2004: 5k mile service
7/17/2004: Flat repaired at Big O ($19.00)
9/16/2004: 10k mile service
Replaced Brake Pedal assembly
Check engine light
Reprogrammed PCM with new updates
Sticking EGR Valve
Replace a malfunctioned EBP Sensor
3/17/2005: 15k mile service
6/21/2005: 20k mile service
11/22/2005: 25k mile service
2/24/2006 – 2/28/2006: Both dead batteries were replaced
Corrected recall of control module – reprogrammed module
Transmission concerns (transmission has delayed engagement into reverse) – nothing found by service tech
Replace burned out license plate light bulb
5/2/2006: Replace cracked dash panel
30k mile service completed
Check engine light
Service record shows EGR Valve and or gasket need to be replaced
EGR Valve replaced
5/17/2006: Brought in to have ordered dash panel above radio (deformed) replaced
7/12/2006: Check engine light
no diagnosis determined
7/20/2006 – 7/21/2006: Check engine light
Service record shows EGR Valve and or gasket need to be replaced and EGR Valve is sticky and out of range at times
Replaced EGR Valve
Cleaned MAF sensor
Replaced Valve ASY - Modulator
7/28/2006: Check engine light
IAT2 Sensor contaminated. Tech cleaned
8/21/2006 -
8/23/2006: Check engine light – came on after driving on freeway approximately 1 hour – light stayed on ever since
EGR Cooler cracked internally
Found sticky tar substance on EGR Valve
35k mile service completed
New wipers installed
EGR cooler assembly replaced
Intake manifold replaced
IAT2 Sensor
EGR valve cleaned (system recommended remove and install or replace)
Air charge temp sensor replaced
Sensor EEC Mass Air replaced
Intake manifold replaced
10/3/2006 – 10/10/2006: Replaced Brake Pedal assembly (second time)
Replaced cracked arm rest
Tightened loose swing open door stops on both sides
(Began working with -------- Ford Management and Ford Corporate: ---- --------, ---- ------------, etc)
10/17/2006: Transmission concerns when coming out of park
Cruise control doesn’t shut off
Replaced br light sw (?)
5/21/2007: While going in reverse the vehicle started to ---- ($100 deductible)
12/26/2007: Replaced wipers
Corrected worn brakes and replaced all brake pads
50k mile premium service done
Purchased 4 new tires at cost of $873.39
7/7/2008 – 7/9/2008: Check engine light - Turbo was sticking, performed Turbo clean procedure
Overhead console with MPG not working and was replaced (replaced with wrong part as old part is obsolete) deductible $200
8/18/2008 – 8/19/2008: 55k mile Oil Change ($115.02)
Weak crank and needles bounce
Both batteries failed and were replaced (deductible $100)
Replaced alternator assembly
11/5/2008 - 11/6/2008: A/C compressor shaft seal is leaking and was replaced
Rear A/C low side lines is leaking and was replaced (deductible $100)
Recharged A/C
11/12/2008: Check engine light
EGR Valve replaced
Front Passenger window regulator assembly replaced
3/17/2009: 60k mile service and oil change ($579.08)
07/22/2009: Check engine light
EGR Valve replaced (after bringing it to the attention of -------- Ford that this had been replaced in November, 2008 they agreed to waive the cost of this)
CAC hoses and tubes leaking
CAC hose and tubes replaced ($571.30)
07/30/2009: Check engine light came on (12 miles outside of Las Vegas as we were just starting a family road trip. Took it into ----------- Ford on 7/31/09)
Diagnostic done ($115.00), no work done because we were on a road trip
Diagnostic Message: Verified MIL M/T Fair KOEO P0401 EGR Self Test and Turbo Road Test EGR Test pass Boost test failed.
After getting vehicle back, the check engine light was no longer on
08/02/2009: Check engine light came on while on road trip – not able to have it checked
08/05/2009: Check engine light went off on its own
08/12/2009 – 8/18/2009: Oil Change ($95.74)
Fuel leak repaired (waived charge due to possibility this was caused by EGR replacement)
“----” recommended (from the 800#) that the air box be replaced with a 2006 version at an estimated cost of $400+. ---------- waived this charge for us and changed it.
2/2/2010: Excursion had been starting sluggishly for the past week. -------- scheduled appointment and took it in. Diagnostic determined one of the batteries was low.
One battery was replaced. Prorated cost was $56.75 plus tax.
3/8/2010: As ------ was trying to leave school, the car would not start. Almost 2 hours later, it finally started.
3/9/2010: Vehicle started fine in the morning, at approximately 9am, the truck would not start again. After numerous attempts, it finally started and ----- took it into ------ Ford.
3/9/2010 – 3/19/2010: Replace High Pressure Oil Pump,
Replace worn out intake gasket & seals,
Replace broken off ground at FICM.
Rental car tax cost us $59.89
Also had Oil changed ($87.64) and Power Steering Flush (cannot determine total price on invoice) Total paid for visit $235.64
3/23/2010: Vehicle would not start and had to be towed to --------- Ford
3/24/2010: ------ called ---- around 5pm to find out the status of the vehicle. ---- told ----- that it is an electrical engine harness, which is not covered by the warranty. Because work was just recently done, ---- was talking to ----- who was contacting corporate to see what they could do to help us out. Later that evening, around 6:15pm, ----- called back and talked to ----- ---------- and expressed concern about the recall of the harness from June, 2005 and the possibility of the broken FICM harness that was done during the work completed last week. Also asked for advice on possibly fixing this matter and/or getting a different vehicle of similar value. ----- said she is working with corporate to help pay for the current problem, but she has been with the company long enough to know they are not going to give us another vehicle. She stated we had missed Ford’s two-year timeframe for replacing a defective vehicle. She pulled the work history and, although she admitted she did not have time to look over everything, she looked at an overview of all the recall work done on the vehicle and recognized the fact we had been into their service department on a regular basis. She agrees we have extenuating circumstances that are not normal. Multiple times she recommended if we do not mind getting a truck, Ford is getting ready to do a big rebate promotion on their trucks. She stated she would talk to their salesperson in charge of trade-ins. She also confirmed that the maintenance/warranty history on this vehicle would not negatively impact the trade-in value. In closing, she stated she would know more tomorrow (3/25) and she would be in touch.
3/25/2010: ----- received a call from a salesperson (---- -------) at ------- Ford who discussed the options for buying a new vehicle.
----- never heard from ----- so he called her in the early afternoon and she said the contact she was working with at corporate denied any help. Due to the service history of this vehicle, ----- has escalated the issue to that person’s supervisor. We returned the rental car to Enterprise since ----- was going out of town (approx $13.00)
3/26/2010: ----- stopped by ------- Ford to pick up any remaining maintenance receipts. She also dropped off a copy of this overview of service with ---- to provide to -----.

 

I checked the CAC boots and they looked to be in good shape. No cracks, all of the clamps looked to be in the right location on the boots and tight.

Checked the FICM voltage per the write up in the tech folder. Got 48.7 on the first test, 49.2 on the second and 48.9 while cranking it over.

Went looking for the green o-ring on the crank case vent elbow. Pulled the elbow out of the valve cover and the o-ring was missing, gone........

Will be looking for a new o-ring tomorrow and see if that takes care of the code coming back.

Will keep you all posted.

Dave

 

Replaced the o-ring on the the elbow and put everything back together yesterday (Friday). Cleared the code. So far so good.

Dave

 

thank you for posting let me know what happens in a few more days.
looks like this has been an ongoing issue that may be able to fix for what $3.00

 

The dealer dinged me $7.69 plus tax.
I have a International Parts and Sevice Center near by. Think I will check them out the next time.

Dave