98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
Ford Forum Ford Forum

» Auto Insurance
» Featured Product
ยป Wheel & Tire Center

Go Back   Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > Ford Trucks | Utes | Vans |SUVs | Crossovers > Ford F-100 | Ford F-150 | Ford F-250 | Ford F-350 | Ford Super Duty | Ford Diesel
Register Home Forum Active Topics Photo Gallery Auto Loans Garage Mark Forums Read Auto Escrow

Ford F-100 | Ford F-150 | Ford F-250 | Ford F-350 | Ford Super Duty | Ford Diesel Forum for discussion of the Ford F100, F150, F250, F350, Superduty and Diesel trucks.

FordForums.com is the premier Ford Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 08-05-2011, 13:10   #1 (permalink)
Registered User
 
Join Date: Apr 2011
Posts: 56
98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

I have 158K miles on my f150 and i just got the motor rebuilt due to the cats being so clogged up it burned every valve in the engine. So KEEP IN MIND THERE ARE NO CATS ON IT. Just a Flowmaster.

The truck is running rough at idle, and a couple times it actually died on me while puling up to a stop light, when getting up tp speed i feel it slowing down for a second then speed back up, gas mileage is around 11 - 12 Average.

I have cleaned the throttle body and a whatever i could clean out of the intake manifold, and MAF sensor, still nothing.

I already tried to change the DPFE but nothing happened, so i took the part back to autozone, and i exchanged it for the EGR Vacuum Solenoid, still not doing anything, Now since i left the New solenoid on, the truck throws the P1401 and P0303 codes.

I'v cleaned the EGR valve numerous times, lines have all been replaced, except the one on the back of the TB. And still nothing..

Could having no CATS cause any of these problems? Im lost

Thanks
Jasenford89 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 08-05-2011, 17:51   #2 (permalink)
2002 F150 XLT
 
Bert's Avatar
 
Join Date: Nov 2008
Location: Oregon
Posts: 9,803
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

Have you checked for vacuum at the EGR valve at idle? There shouldn't be any. How about the lines from the exhaust to the DPFE? are they clear.
__________________
Bert
Bert is offline   Reply With Quote
Old 08-05-2011, 18:22   #3 (permalink)
Registered User
 
Join Date: Apr 2011
Posts: 56
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

as far as checking vacuum from the egr.. are you talking about the green line that goes on the top of the Valve or vacuum coming from the little nipple on the valve? There was no vacuum at idle for the actual line, but there was before i replaced the EGR Vacuum solenoid.

Ya there clear and brand new
Jasenford89 is offline   Reply With Quote
Old 08-05-2011, 20:34   #4 (permalink)
2002 F150 XLT
 
Bert's Avatar
 
Join Date: Nov 2008
Location: Oregon
Posts: 9,803
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

The EGR valve may be sticking open a little and that will make it stall or run rough.
__________________
Bert
Bert is offline   Reply With Quote
Old 08-06-2011, 08:26   #5 (permalink)
Registered User
 
Join Date: Apr 2011
Posts: 56
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

Would it be stuck if i was still able to put a line on it and suck through the line and the truck stumbles?
Jasenford89 is offline   Reply With Quote
Old 08-06-2011, 11:55   #6 (permalink)
2002 F150 XLT
 
Bert's Avatar
 
Join Date: Nov 2008
Location: Oregon
Posts: 9,803
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

If it sticks open when it's suppose to close.
__________________
Bert
Bert is offline   Reply With Quote
Old 08-06-2011, 15:48   #7 (permalink)
Registered User
 
Join Date: Apr 2011
Posts: 56
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

alright, makes sense.. is there any way to test it, I,v taken it off several times to clean it, if i really had to i guess i could just go buy one real quick and see what happens..

Would this cause the misfire also?...

I swaped the ignition coils to the different sides, nothin, and i also took the spark plug out of the number 3 cyl (Misfire) and swapped it with the number 2 cylinder (good) but still nothin, im going to check the wires in a bit
Jasenford89 is offline   Reply With Quote
Old 08-06-2011, 17:15   #8 (permalink)
2002 F150 XLT
 
Bert's Avatar
 
Join Date: Nov 2008
Location: Oregon
Posts: 9,803
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

You could set a thin piece of metal in the gasket area and run it. It wouldn't cause a misfire. That's a different problem.
__________________
Bert
Bert is offline   Reply With Quote
Old 08-07-2011, 13:37   #9 (permalink)
Registered User
 
Join Date: Apr 2011
Posts: 56
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

ok..

Well i reset the computer and right now its only telling me p0401 and p0303 and the was about a two hundred mile day.

For some reason i never checked the #3 plug wire as far as putting a screwdriver in it and checking for spark and sure enough no spark so im just going to buy a wireset today.

For the P0401 ill just buy the EGR valve and see what happens... Could a vacuum leak cause this code, because i no there is a leak somewhere becuase my air blows through the dash?
Jasenford89 is offline   Reply With Quote
Old 08-16-2011, 16:17   #10 (permalink)
Registered User
 
Join Date: Aug 2011
Posts: 165
Re: 98 f150 4.6 DTC 1401, 0303, 0401, 0402 problems

The 401 code is a low flow test code.
The tract between the exhaust manifold to the outlet of the EGR cannot flow the required amount of exhaust when tested by the computer.
The pipe orfice may be plugged, the EGR is not opening or the ports behind the EGR are plugged with carbon.
Also if the DPFE cannot read the pressure and send it to the computer the code 401 is the result.
Don't take anything apart until you do a simple test.
Apply enough vacuum to the EGR to open it a small amount.
If the egr opens and the ports are open the idle will roughen up. This means the EGR and ports behind it are open and good.
Then you look at the DPFE as being faulty or the vacuum regulator that supplies vacuum to the EGR is not working when commanded to open.
To replace DPFE, use only a Ford part.
The 303 code likely is a faulty coil.
Good luck.
Bluegrass is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > Ford Trucks | Utes | Vans |SUVs | Crossovers > Ford F-100 | Ford F-150 | Ford F-250 | Ford F-350 | Ford Super Duty | Ford Diesel



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Powered by vBadvanced CMPS v3.2.2

All times are GMT -7. The time now is 03:45.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.6.0
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.