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Hi, quick question on the location of the EGR valve on a 2001 F150 with the 4.6 or 4.7L (small V8) engine.  My daughter's truck started acting like it was missing on one cylinder, according to her description, when she left work a few days ago.  I told her to leave it in town and I'd check it the next morning.  When I drove in to look at it the truck started just fine, no misses.  She came in later that day and drove it home but said it did act up a little on one of the stops she had to make on the way.  I rented a code reader from AutoZone and it said the P0401, P0402 and P1401 codes had been recorded all of which seem to be associated with the EGR.  

AutoZone is usually very good at putting up decent descriptions and diagrams of engine component locations but this time it's lousy! I did not see any listing of an EGR valve in any of the diagrams of the general engine description and zip, zero, nada on the EGR description itself.  Is it under the plastic hood on the top of the engine or buried in the back of the intake manifold?

Thanks ahead of time!  

first..

you are going to want to download this 63 page file on HOW THE SYSTEM thinks..

http://www.motorcraftservice.com/vdirs/diagnostics/pdf/obdsm109.pdf


usually with the P0401 codes...  the DPFE sensor or the EGR vacuum solenoid need to be replaced..


if your DPFE sensor is aluminum ... change it to one of the black plastic replacements... they are a vastly improved design...

instead of a diaphragm moving back and forth to break or corrode.. it simply uses two pressure sensors ...  sends the same signals...

Duralast/EGR Valve Pressure Sensor
For your 2001 Ford Truck F150 1/2 ton P/U 2WD 4.6L EFI
Part Number: SU2308




Duralast/EGR Vacuum Solenoid
For your 2001 Ford Truck F150 1/2 ton P/U 2WD 4.6L EFI 8cyl
Part Number: EVS58




why change them... because MOST of the time the originals are bad...

i can change similar versions on a taurus in under 10 minutes on a HOT motor..   you have a plastic cover to remove...  

try not to drop the tiny nuts that hold the egr vacuum solenoid to its bracket...   use an 8mm or 5/16  1/4 drive probably deep socket... a shallow socket may also fit...

you will have to clear the codes also. with the scan tool...

if the EGR vacuum solenoid fails..  or hangs up

it will sometimes allow manifold vacuum to hold the EGR valve open at idle and cause your misfire..  

Hey!  Thanks Wayne.  Good to hear from you again.  I downloaded the .pdf file and also found the parts in question.  The DPFE sensor sure looked familiar and, sure enough, I'd replaced it a year or more ago with the plastic body type.  I'd gotten a code on it and replaced it easily.

I'll also replace the solenoid if they're that prone to problems and see if that doesn't clear things up.  If not, then the valve itself gets a permanent vacation!

Thanks again.  

read your other EGR post...

don't trash the EGR system...   you won't like the reduced fuel economy... the check engine light glaring in your face.. or the Melted pistons...

egr flow has 13 percent oxygen
fresh air into the engine has 21 percent oxygen.. so the EGR flow reduces the oxygen content.. lowering the combustion temps..  requires less fuel to reach optimal air fuel ratios... actually increases fuel economy slightly... and reduces the NOX emissions from the engine...


i have a private message for you...  

Well, I'm now the proud owner of an ODB-II scanner/reader.  Tried to get AZ to scan and clear the codes on my daughter's truck but their policy says they can't clear codes, which seems dumb if they're just going to reset themselves if the problem isn't fixed.  It's the middle of the road scanner - Actron CP9575 that lets you scan, read and clear codes and also is updateable on the Internet plus some other things.  The top of the line scanner required another one of Ben's famous portraits so I hope the extras I opted out of won't matter in the long run.

I'll clear the codes on the truck when she comes home tonight and see if they come back to haunt us.

Thanks  

I put the code reader on the truck and cleared the codes then took it for a test drive.  When I checked the codes again the P0401 code came up again but didn't set the Check Engine light.  Other than that it ran better than its run in a long time. No other codes presented themselves but there were a lot of readings that I need to study up on that the reader was putting out while on the test drive.  Apparently I did not perform a qualifed test drive or something to that effect.  It said to check the owner's manual to find out how to do that for diagnostic purposes.  

was that 9575 like 130 bucks..

as some scan tools actually display GRAPHED sensor  voltage signals like this..  i have not tried it on the EGR control.. that probably takes a really expensive unit..



it looks like a decent scan tool..  see if it has a graph display for things like the oxygen sensors..

a c t r o n... is actually   S P X company who make professional versions that get way expensive under the OTC brand..  so the functions are limited.. or the mechanics would buy the 130 buck scan tool instead of the $2500 and up buck scan tool..

i use the 130 buck harbor freight 98614 all the time...

i have an earlier OTC monitor extended i picked up off the net for 300 bucks thats a full functional obd1 and up to 98 obd2 model..

you can still do the vacuum gauge test.. with one of these...    to see if the EGR valve is actually receiving signal..



please .. also look around the intake for elbow shaped vacuum hoses.. do this with the engine idling.. feel them.. check for collapsed sections from the vacuum pulling them in..  usually a code P0171 or P0173 i think will set..

i have had to change a bunch of them on the 5.4 motors in navigators..

i have found that the dorman 46002 at most parts stores can be cut in half off center.. can be used to replace many of the elbows that are bad around the upper intake..

 

Well, the Check Engine light did reset itself yesterday so, before I have my daghter pick up a new EGR valve I'll do the checks you talked about in your last.  She said it did the stuttering and shaking bit again yesterday.

Thanks.  

Ok, the two codes that were set were P0401, low or no flow on EGR valve, and P0305, cylinder 5 misfire.  I think I may have screwed up, however, and not inserted the electrical plug far enough in to the socket so the solenoid couldn't work.  I reinserted the plug and made sure it bottomed out and the plastic clip engaged this time.  I pulled the vacuume line off of the EGR valve and made a connection to my vacuum gage with a straw between it and that line.  I ran the engine up in rpm's slowly but there wasn't any vacuum showing on the gage until it hit 2500 rpm and above.  At that point it began to creep up so, hopefully, this will fix this problem.

I checked the vacuum lines on the rest of the engine that I could see and the only one that looked bad, but still not leaking, was one that connected to the top of the intake manifold and ran over to some kind of diaphragm solenoid valve on the firewall just above the brake booster.  The heat has dried the outside of the rubber line and it won't last much longer.  It's a 3/8" line so it'll be a big leak when it goes.  

if you get a P0305 again... check the coils and the coil boots.. for signs of high voltage leaks..





 

Here's hoping I don't.  I replaced the coils for #1 and #5 cylinders on my dad-in-law's '98 F150 with the 5.4L engine and the #1 coil just about made me go apoplectic! I think you helped me through that ordeal, too. Thank goodness #5's up front.  

I do not want to try changing plugs, though, after reading about the horror stories of breaking the dang things off in their holes!  

it depends upon which 4.6 it has..

this is the spark plug for it.. so it should be straight forward..

the 5.4 is a 3 valve motor... and it uses a ODD ball spark plug... that is the one to break loose with an inch pound spring type torque wrench.. after blowing out the top of the spark plug area with compressed air on a LONG nozzle.. then let it soak in the cleaner that was mentioned overnight to soften the carbon

i would bet that one might be able to create something like the expanding device that fits on the end of the gardern hose to flush the sewer lines..  to allow solvent to be forced through the threads of the slightly loose spark plug..  

Ok, just to make sure, the #5 cylinder is always the driver's side front cylider isn't it?  

Well, I'm relieved to report the misfire code was not reset (coils are under the fuel rails) but the P0401 and P1401 codes were.  The DPFE was said to have had a high voltage error so I guess replace the DPFE device before replacing the EGR valve itself?