P401 Fix?
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P401 Fix?
Has anyone poured the Seafoam liquid straight into their oil?
I am trying to fix a P401 problem and don't know what to do next! I have changed the EGR valve, checked to make sure there is vaccuum at the PCV valve, cleared the codes, but can't get the check engine soon light to stay off. I also ran a tank of 93 octane with a can of seafoam cleaner, but to no avail.
Anybody have any suggestions on what to try next? Should I attempt to pour a quarter can or so into my 4.6L V8 engine oil? Is it recommended to run this stuff in my oil for the next 3K (just got my oil changed)?
Thanks for any suggestions......
I am trying to fix a P401 problem and don't know what to do next! I have changed the EGR valve, checked to make sure there is vaccuum at the PCV valve, cleared the codes, but can't get the check engine soon light to stay off. I also ran a tank of 93 octane with a can of seafoam cleaner, but to no avail.
Anybody have any suggestions on what to try next? Should I attempt to pour a quarter can or so into my 4.6L V8 engine oil? Is it recommended to run this stuff in my oil for the next 3K (just got my oil changed)?
Thanks for any suggestions......
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there are more things you can try, did you see the other thread on the same page about p0401. If not check it out.
I used Sea foam in my truck to get rid of a hesitation, I used it by sucking it up to pcv vaccume line 1/3 can. then let set for 15 min then start up and drive for 30 min will white smoke but that is ok. cleared my problem.
any way check out the other thread it will probably help.
Lance
I used Sea foam in my truck to get rid of a hesitation, I used it by sucking it up to pcv vaccume line 1/3 can. then let set for 15 min then start up and drive for 30 min will white smoke but that is ok. cleared my problem.
any way check out the other thread it will probably help.
Lance
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I did what the can of seafoam said and dumped 1/3 of the can in my crankcase(with great reluctance) and drove about 250 kms and drained the oil, I've been running mobil1 oil in my truck for some time now and during regular intervals changes never really had to dirty of oil, but after only that short time with seafoam in the engine it was almost black(yikes!). No problems since but I dont think I will do that again just because of such dramatic results and I wont push my luck again. Also I didnt notice any improvement in the way the engine ran, so use at your own risk.
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I did not follow the instructions on thecan I was told to let the pcv valve tube to the manifold suck up the or1/3 can of sea faom. Then shut vehicle off and wait 15 min them run truck for about 30 min. the way you did it, it cleans the crank case and oil gallies and heads. The way I did it, it cleans the valves and piston heads and cylinder area along with the intake manifold. Just a stronger dose then running it through the gas tank.
It worked so well on my Ford F150 with 108,000 miles that I used it on my daughters honda and my sons Toyota. all three run alot better.
Now I'm sorry you don't trust sea foam, but it did it's job in the crank case and cleaned it all up. You are better off with it clan believe it or not.
Anyway I beleive inthe stuff.
Lance
It worked so well on my Ford F150 with 108,000 miles that I used it on my daughters honda and my sons Toyota. all three run alot better.
Now I'm sorry you don't trust sea foam, but it did it's job in the crank case and cleaned it all up. You are better off with it clan believe it or not.
Anyway I beleive inthe stuff.
Lance
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From: Louisville,Ky.
The most common reason for the P0401 is a bad egr sensor. To check the egr, with the engine idling, remove the egr vacuum line an put vacuum to the egr valve, if the engine tries to stall, then the egr is working properly and the sensor is probably bad.
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From: MI, USA
yes, this code is a %@#&!
here's our recent woes with it...
https://www.ford-trucks.com/forums/s...d.php?t=395544
...you said you did get a vacuum at the pvc when you pulled it?
whether you did or didn't go back to the pvc valve and check the hose where it bends back around under firewall back in to the intake... look for a collapsed / cracked hose all the way along the hose until it runs back into the intake.
also, check the ends... the end the connects to the PVC valve and the end opposite end that connects to the intake. the softer rubber ends that connects the hose to the PVC and intake - they can get to soft over time and start collapsing and even though you have some vacuum at the PVC valve - it's insufficient.
lastly, if you are mechanically inclined, do yourself a favor and follow these instructions to clean the throttle body and ALL the ports. i followed my own version (without removing the throttle body) and i'm now going back to do it right
...throttlebodyclean.php
good luck!
here's our recent woes with it...
https://www.ford-trucks.com/forums/s...d.php?t=395544
...you said you did get a vacuum at the pvc when you pulled it?
whether you did or didn't go back to the pvc valve and check the hose where it bends back around under firewall back in to the intake... look for a collapsed / cracked hose all the way along the hose until it runs back into the intake.
also, check the ends... the end the connects to the PVC valve and the end opposite end that connects to the intake. the softer rubber ends that connects the hose to the PVC and intake - they can get to soft over time and start collapsing and even though you have some vacuum at the PVC valve - it's insufficient.
lastly, if you are mechanically inclined, do yourself a favor and follow these instructions to clean the throttle body and ALL the ports. i followed my own version (without removing the throttle body) and i'm now going back to do it right
...throttlebodyclean.php
good luck!
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Thanks for the replies and suggestions.
LxMan1 - you are suggesting sticking my finger or something else over the nipple where the vacuum hose plugs into the EGR, right?
I believe that I will try the Seafoam through the PCV valve after running it through the tank. Also, thanks for the throttle body cleaning link...definitely getting a vacuum at the PCV so this may be my next attempt!
LxMan1 - you are suggesting sticking my finger or something else over the nipple where the vacuum hose plugs into the EGR, right?
I believe that I will try the Seafoam through the PCV valve after running it through the tank. Also, thanks for the throttle body cleaning link...definitely getting a vacuum at the PCV so this may be my next attempt!
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Brett Foote
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Joined: Nov 2004
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From: MI, USA
hey, i finally took of the throttle body and immediately saw where the ports were clogged -- and i mean totally clogged with the stuff pouring out of the egr ports and stuck to the inside of the throttle body - you had to see it to believe it.
she's running as good as she ever had right now! guess it's time to address this exhaust issue now.
can anyone recommend a nice exhaust from the catalyst on back for a 1998 Expedition?
she's running as good as she ever had right now! guess it's time to address this exhaust issue now.
can anyone recommend a nice exhaust from the catalyst on back for a 1998 Expedition?
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p401
hi i have 98 ranger i hust fix the problem just change the EGR PRESSURE SENSOR OR make sure the vaccum hoses not broken also clean the small
pipe make sure dont have carbon also see if you can go to autozone to erase the codes if you dont have a code reader i hope this will help you it work for me
pipe make sure dont have carbon also see if you can go to autozone to erase the codes if you dont have a code reader i hope this will help you it work for me
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