Got the "Service Engine Soon" light...since my wife was driving it at the time and I was at work, I asked her to swing by Autozone and have the codes read. They reported "insufficient EGR flow" but for whatever reason they couldn't or wouldn't give her the actual DTC number.

Anyway, I took a chance based on my reading here, and replaced the DPFE sensor. However the SES light is still on. Should it go out immediately if the DPFE sensor was the culprit, or does it need to be reset, and if so how? Temporarily disconnect the battery?

I have not yet checked or cleaned the EGR port in the throttle body that I have read about here, so if the DPFE sensor was not actually the culprit, I guess that is my next step.

 

the cel has to either be cleared or you'll have to do like 100 key cylcles and drives. meaning you'd have to turn the key on and drive like 100 times before it'll go out. to clear it you can either disconnect the battery then turn headlight switch on for ten minutes. that or she can stop by autozone and have them cleared.

 

My experience with the P401 I think it is code was I replaced the DPFE EGR only for it to turn out to be the tube going into the exhaust manifold was clogged. You should ream that out real good. The reset the truck like Matt said. Autozone told me they will no longer reset. You have to do it by disconecting the battery.

 

Nonsense. The next time the OBDII EGR monitor runs and passes will cause the PCM to turn off the SES/CEL. There is no provision for cycling the key 100 times or anything of such a nature.

Either use a code scanner to reset, remove the PCM KAM fuse for 10 minutes, or disconnect the battery negative terminal for 10 minutes. I recommend pulling the fuse if a scan tool isn't available since that will make it so you don't have to reset the clock and radio presets and doesn't require any tools.

SM: Perform a vacuum test on the EGR valve at idle. If the engine speed doesn't drop, the ports are clogged. Hopefully, you bought a Motorcraft DPFE sensor, not the AZ junk.

Steve

 

I tried the battery disconnect for about 30-45 minutes last night. Upon cranking the engine afterwards, the SES light was out, but it was late so I only let it run a few minutes...didn't wait a long time to see if it would come back on. We'll see what happens today when the wife is running around town. Interestingly, the radio kept all the station presets, but I did of course have to reset the clock. Perhaps the presets are kept in some sort of long-term memory.

Although I had researched here enough to suspect the DPFE sensor, I had not yet gotten to the numerous recomendations to use the Motorcraft part. I got one from NAPA, which I had always heard through the grapevine is usually a step above Autozone, Advance ,etc. in quality. Even if that is wrong, now that I know what's up with the sensor, it won't be that big a deal if I have to replace it again soon (with a Motorcraft part)

 

Usually takes a few drive cycles to get the DPFE (p401) code back. Give it a week if its not back your probably good for now.

 

That's strange about the pre-sets. I wouldn't trust that re-boot. Personally, I would disconnect and pull the fuses. Then hit the light switch. See what happens with the pre-sets then. That receiver must have a healthy capacitor/capacitors incorporated.

Yea , I would go with Motorcraft on the 01.

 

hey, my wife is the primary driver, and is not currently employed full-time. She may be a "mom" but she is not one of those "stay-at-home moms". She is always runnin' the roads .

In other words the truck might easily get a few drive cycles today, and several more tomorrow, and the day after that, etc, etc. I figure if the SES light is not back on by tomorrow night, I'm golden .

 

I've had it stay off for several hundred miles after a reset. Dont be surprised if it comes back after a few days.

 

Leaks are tested at start up. 3 drive cycles on the rest.

 

..and each "drive cycle" must be separated by an 8 hour cold-soak. Multiple trips on the same day don't constitute separate drive cycles.

It takes TWO consecutive failures of a monitor to set the MIL to on.

Steve

 

Yea , I didn't realize consecutive included cold soak. Well which one is 3 failures before the light ? That must be the cat checkers then (before 420 or 30 is set).

 

It varies depending on the vehicle and year. Certain cat evaluation procedures only take two consecutive failures, others require three to six.

Go to www.motorcraftservice.com and download the appropriate OBDII manual so you can research it.

Steve

 

Yea, that stuffs just hard to remember unless your constantly fooling with it. :o

I have two different downloads on the shop computer. Ones from Scorpio (old) and the other is the MC manual.