Check Engine light-code #P0401

Everything to do with engines, options, upgrades.
Post Reply
retiredtim
Posts: 77
Joined: July 18th, 2016, 9:50 am
Location: Goffstown, New Hampshire

Check Engine light-code #P0401

Post by retiredtim »

Anyone having problems with check engine light? I've replaced EGR valve, EGR sensor & checked the two hoses for leaks. I've reset the light but keeps coming on after about 100 miles.
HereComesTrouble
Posts: 28
Joined: June 19th, 2016, 9:16 pm

Re: Check Engine light-code #P0401

Post by HereComesTrouble »

retiredtim wrote:Anyone having problems with check engine light? I've replaced EGR valve, EGR sensor & checked the two hoses for leaks. I've reset the light but keeps coming on after about 100 miles.
A lot of information to be found here:
https://www.google.com/webhp?sourceid=c ... code+P0401
deppstein
**Forum Contributor**
Posts: 357
Joined: July 13th, 2015, 7:07 am

Re: Check Engine light-code #P0401

Post by deppstein »

We did have a check engine light issue on our trip this summer to the Gaspe Peninsula of Quebec. After reading the manual, I thought it was an indication of low octane gas (Canada does not measure octane by the dual method that we do. So, I switched from the usual 87 to a higher octane. After a couple of hundred miles, it went out...so I figured that I was all set.

BUT, on last trip out to Ohio in September, it came on again, and stayed on. So, I took it to a Ford dealer in the Youngstown area, and they quickly diagnosed it as a corroded line from gas tank to the on-board generator that was leaking ever so slightly (even showed it to me). Replacing the line entailed dropping the gas tank, so it was NOT cheap...$1,000+ all-in. They also replaced a sensor (can't remember which one, but I have the slip out in the Rig if you want/need to know). Has been more than three more weeks of constant travel and I have not had any check engine light (or other) issues.

Hope this helps.

David
User avatar
Blue~Go
Senior Member
Posts: 3716
Joined: July 31st, 2014, 1:01 am
Location: 1999 Concourse

Re: Check Engine light-code #P0401

Post by Blue~Go »

I've had a number of #P0401 codes as well. And I've also had EGR work done, but that didn't seem to change anything (grrr). So far no-one has been too interested in diagnosing/repairing it, but it bugs me. I also get #P0455. I'll be in a place this winter where there is a mechanic I trust to work on it (these codes don't bring drivability issues, but of course still want to fix issues).

I can clear the codes with the ScanGauge. That doesn't mean the problem goes away of course, but it can be helpful to see when they come on as a diagnostic. In my case it seems to have something to do with heavy vacuum use (i.e. accelerating up hill while towing with A/C on).

I didn't say anything when you first posted because I didn't have any really good info to share, and was hoping someone else would respond with some (as I have the same questions!).

David: Did you get the #P0401 code or was it just "a code" (i.e. check engine light) that you couldn't tell the number of (you need a ScanGauge or similar reader to actually see what code it is). I just wondered because if it's a different code then it's likely totally unrelated, but of course if it IS #P0401 (or #P0455) then it's applicable.
1999 Concourse
Post Reply